How to prove [...] the communication, or the harmony of two substances as different as the soul and the body.
1696
Source: Second Clarification of the System of Communication of Substances
Gottfried Wilhelm Leibniz
Gottfried Wilhelm Leibniz (1 July 1646 – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist, and diplomat. He is a prominent figure in both the history of philosophy and the history of mathematics.
Imagine two clocks or watches that are in perfect agreement.
1696
Source: Second Clarification of the System of Communication of Substances
Now, put the soul and the body in the place of these two clocks; their agreement can happen in one of these three ways.
1696
Source: Second Clarification of the System of Communication of Substances
The way of influence is that of the common philosophy; but, as one cannot conceive of material particles that could pass from one of these substances to the other, this view must be abandoned.
1696
Source: Second Clarification of the System of Communication of Substances
The way of the Creator's continual assistance [...] is to introduce a Deus ex machina into a natural and ordinary matter [...].
1696
Source: Second Clarification of the System of Communication of Substances
[The Creator] should only concur in the way that he concurs in all other natural things.
1696
Source: Second Clarification of the System of Communication of Substances
Thus, there remains only my hypothesis, that is to say, the way of harmony.
1696
Source: Second Clarification of the System of Communication of Substances
God made each of these two substances from the beginning of such a nature that, by following only its own laws [...], it nevertheless agrees with the other [...].
1696
Source: Second Clarification of the System of Communication of Substances
[The substances agree] just as if there were a mutual influence, or as if God always had a hand in it beyond His general concurrence.
1696
Source: Second Clarification of the System of Communication of Substances
After that, I need not prove anything, unless one demands that I prove God is skillful enough to use this preemptive artifice.
1696
Source: Second Clarification of the System of Communication of Substances
You see clearly that this way [of harmony] is the most beautiful and the most worthy of Him.
1696
Source: Second Clarification of the System of Communication of Substances
You suspected that my explanation would be opposed to the very different idea we have of the mind and the body; but [...] no one has better established their independence.
1696
Source: Second Clarification of the System of Communication of Substances
While we have been obliged to explain their communication by a sort of miracle, we have always given reason to fear that the distinction between the body and the soul was not as real as is believed.
1696
Source: Second Clarification of the System of Communication of Substances
It seems to me that this is saying the same thing in other words, as those who claim that my will is the occasional cause of the movement of my arm, and that God is the real cause of it.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[...] according to you, every time I want to raise my arm, it is the will of God that is the real and efficient cause of this movement.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[...] the essence of the body cannot be extension, but every body, besides extension, must have a substantial form.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
You claim that every substantial form is indivisible, indestructible, and ungenerable, and can only be produced by a true creation.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
All this amounts to saying that all bodies whose parts are only mechanically united are not substances, but only machines or aggregates of several substances.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
it follows that, apart from man, there would be nothing substantial in the visible world, because substantial unity requires a being that is [...] indivisible, and naturally indestructible [...].
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[...] it is a paradox to say that there is nothing substantial in a block of marble, since this block of marble is not the mode of being of another substance.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[Bodies] would doubtless be something imaginary and apparent only, if there were nothing but matter and its modifications.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I see no problem in believing that in all of corporeal nature there are only machines and aggregates of substances [...].
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[...] the thinking or spiritual substance is [...] much more excellent than the extended or corporeal substance, [for] only the spiritual one has a true unity, and a true self, which the corporeal one does not have.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[...] all the phenomena of bodies can be explained mechanically [...] without bothering to know whether there are souls or not.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
What about worms which, being cut in two, each part moves as before? If a fire broke out [...], what would become of these [...] indestructible souls?
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is agreed that [the soul] has a true and perfect unity and a true self, and that it communicates in some way this unity [...] to the whole composed of the soul and the body which is called man.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is no less true that [the body's] parts are only mechanically united among themselves, and thus it is not a single corporeal substance, but an aggregate of several corporeal substances.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Is it not the greatest perfection they [organized bodies] can have, to be such admirable machines that only an all-powerful God could have made them?
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Error in itself harms neither piety nor friendship.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
These abstract questions require leisure.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[A] generosity [...] which is rare [...] in a first-rate mind, whose reputation usually shields it not only from the judgment of others, but even from its own.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I have learned [...] to prefer the public good [...] to my own particular advantage.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
To often lose a good cause over formalities is a remedy in justice similar to that of a surgeon who would often cut off arms and legs.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
If I dare say so, I claim to thereby advance analysis beyond the Pillars of Hercules.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Nothing is without a reason, or that every truth has its a priori proof, drawn from the notion of the terms, although it is not always in our power to arrive at this analysis.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I reduce all of mechanics to a single proposition of metaphysics.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I do not much approve of the manner of those who always appeal to their ideas when they are at the end of their proofs.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
We often think without ideas by using characters in place of ideas [...], the meaning of which we falsely assume we know.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I hold that the mark of a true idea is that one can prove its possibility, either a priori [...] or a posteriori.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Definitions [...] are real when it is known that the defined is possible; otherwise they are only nominal, which should not be trusted.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
If by chance the defined implied a contradiction, one could draw two contradictory statements from the same definition.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One must distinguish between true and false ideas and not give too much to one's imagination under the pretext of a clear and distinct assertion.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I cannot conceive why one imagines that God is obliged [...] to produce nothing in the universe but what a corporeal machine can produce by simple mechanical laws.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If we say that the sun attracts the earth across an empty space [...] all of this is but a phenomenon or an actual fact, discovered by experience.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
It is undoubtedly true that this phenomenon is not produced without means, that is to say, without a cause capable of producing such an effect.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Philosophers can therefore seek this cause, and try to discover it [...] whether it be mechanical or non-mechanical.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
But if one cannot discover its cause, does it follow that the phenomenon discovered by experience [...] is any less certain and less indisputable?
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Should an evident quality be called occult, because its immediate cause is perhaps occult, or has not yet been discovered?
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If any philosopher can explain these phenomena by the laws of mechanics, far from being contradicted, all learned men will thank him for it.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
To maintain one's conclusion, without proving it [...] I call that begging the question; which is entirely unworthy of a philosopher.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
It is very certain [...] that in general there is a sufficient reason for everything.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The question is whether, in certain cases, when it is reasonable to act, different possible ways of acting cannot be equally reasonable.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If, in these cases, the mere will of God is not a sufficient reason for acting in one particular way rather than another.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[The essence of liberty consists in] a principle of action [...] entirely distinct from the motive or the reason which the agent has in view.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
When the same idea returns to the mind, without the external object that first gave rise to it acting on our senses, this act of the mind is called reminiscence.
1704
Source: New Essays on Human Understanding
If the mind contemplates [an idea] for a long time with attention, it is contemplation.
1704
Source: New Essays on Human Understanding
When the idea we have in our mind floats, so to speak, without the understanding paying any attention to it, this is what is called reverie.
1704
Source: New Essays on Human Understanding
When the mind focuses on an idea with great application, considering it from all sides [...] this is what is called study or contention of mind.
1704
Source: New Essays on Human Understanding
To dream is to have ideas in the mind while the external senses are closed, so that they do not receive the impression of external objects with their usual vividness.
1704
Source: New Essays on Human Understanding
It is sensation when one perceives an external object, reminiscence is its repetition without the object returning; but when one knows one has had it, it is memory.
1704
Source: New Essays on Human Understanding
We pay attention to the objects we distinguish and prefer over others.
1704
Source: New Essays on Human Understanding
Attention whose goal is to learn (that is, to acquire knowledge to keep it), is study.
1704
Source: New Essays on Human Understanding
Reverie seems to be nothing other than following certain thoughts for the pleasure one takes in them, without any other purpose, which is why it can lead to madness.
1704
Source: New Essays on Human Understanding
We can only distinguish dreams from sensations because they are not linked with them; it is like a separate world.
1704
Source: New Essays on Human Understanding
[A vision] is nothing other than a dream that passes for a sensation, as if it were teaching us the truth of objects.
1704
Source: New Essays on Human Understanding
Thought is an action and cannot be the essence: but it is an essential action, and all substances have such.
1704
Source: New Essays on Human Understanding
We are never without perceptions, but it is necessary that we are often without apperceptions, that is, when there are no distinct perceptions.
1704
Source: New Essays on Human Understanding
It is for want of having considered this important point [the small perceptions] that we have remained almost until now ignorant of what is most beautiful in souls.
1704
Source: New Essays on Human Understanding
It is a strange thing to see that many people respond not to what is said to them, but to what they imagine.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
The ordinary analysis of the Cartesians is found to be very inadequate for difficult problems.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Movement in itself, separated from force, is something merely relative, and one cannot determine its subject.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Force is something real and absolute, and its calculation being different from that of movement [...], it is not surprising that nature conserves the same quantity of force.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
There is something else in nature besides extension and movement, unless one denies things all force or power.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[To deny things all power would be] to change them from substances, which they are, into modes; as Spinoza does, who wants God alone to be a substance.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I hold that one created substance does not act upon another in metaphysical rigor, that is, with a real influence.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
[God's] operation is a continual creation, whose source is the essential dependence of creatures.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
In order to speak like other men, who are right to say that one substance acts upon another, one must give another notion to what is called action.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I want to complete my meditations on the general characteristic or universal calculus, which should serve in other sciences as it does in mathematics.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Everywhere I proceed by letters in a precise and rigorous manner, as in algebra.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
There are no authors whose style more closely approaches that of the geometers than the style of the jurists in the Digests.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
How can one apply this calculus to conjectural matters? I answer that it is as Messrs. Pascal, Huygens, and others have given demonstrations concerning chance (alea).
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One can always determine the most probable and the most certain as far as it is possible to know from the given data (ex datis).
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
However funny a thought may seem, it would not fail to be of consequence if it were executed.
1675
Source: A Strange Thought, touching on a new kind of representations
It would be good to have private individuals capable of bearing the necessary costs. For a powerful lord would make himself the sole master of the affair, once he saw its success.
1675
Source: A Strange Thought, touching on a new kind of representations
As a great number gives rise to disorder, I believe the best would be to have only two or three associates.
1675
Source: A Strange Thought, touching on a new kind of representations
The Representation could always be mixed with some story or comedy. [It would be a] Theater of nature and art.
1675
Source: A Strange Thought, touching on a new kind of representations
One could create comedies of the trades, one for each trade, which would represent their skills, oddities, jests, masterpieces, laws, and ridiculous particular fashions.
1675
Source: A Strange Thought, touching on a new kind of representations
The use of this enterprise would be greater than one could imagine, both in public and in private.
1675
Source: A Strange Thought, touching on a new kind of representations
[The project] would open people's eyes, encourage inventions, provide beautiful perspectives, and instruct the world on an infinity of useful or ingenious novelties.
1675
Source: A Strange Thought, touching on a new kind of representations
[It] would be a general bureau of address for all inventors.
1675
Source: A Strange Thought, touching on a new kind of representations
One would soon have there a theater of all imaginable things.
1675
Source: A Strange Thought, touching on a new kind of representations
All respectable people would want to have seen these curiosities, to be able to speak of them.
1675
Source: A Strange Thought, touching on a new kind of representations
The enterprise could have consequences as beautiful and as important as one could imagine, which perhaps will one day be admired by posterity.
1675
Source: A Strange Thought, touching on a new kind of representations
[One must] make the world fall into the trap, take advantage of its weakness and deceive it to cure it.
1675
Source: A Strange Thought, touching on a new kind of representations
Is there anything so just as to make extravagance serve the establishment of wisdom?
1675
Source: A Strange Thought, touching on a new kind of representations
The idea of being, of the possible, of the same, are so innate that they enter into all our thoughts and reasonings, and I regard them as essential to our mind.
1704
Source: New Essays on Human Understanding
We are, so to speak, innate to ourselves, and since we are beings, being is innate to us; and the knowledge of being is enveloped in the knowledge we have of ourselves.
1704
Source: New Essays on Human Understanding
What is natural to us is not for that reason known to us from the cradle; and an idea may be known to us without our being able at first to decide all the questions that can be formed about it.
1704
Source: New Essays on Human Understanding
One begins with the senses to lead people little by little to what is above the senses. However, all this difficulty in attaining abstract knowledge does nothing against innate knowledge.
1704
Source: New Essays on Human Understanding
The brilliant marks of an extraordinary wisdom and power appear so visibly in all the works of creation that any reasonable creature [...] cannot fail to discover the author of all these marvels.
1704
Source: New Essays on Human Understanding
Not virtue itself, but the idea of virtue is innate.
1704
Source: New Essays on Human Understanding
[Truths] are innate, which is to say that they can be found within oneself.
1704
Source: New Essays on Human Understanding
I am of the opinion that reflection is sufficient to find the idea of substance within ourselves, who are substances.
1704
Source: New Essays on Human Understanding
For knowledge [...] to be in our mind, it is not necessary that we have ever actually thought of it: they are but natural habits, [...] active and passive dispositions and aptitudes, and more than a tabula rasa.
1704
Source: New Essays on Human Understanding
It is certain that an infinity of thoughts come back to us that we have forgotten having had.
1704
Source: New Essays on Human Understanding
Often we have an uncommon facility for conceiving certain things because we have conceived them before, without remembering it.
1704
Source: New Essays on Human Understanding
I believe that dreams often renew old thoughts in this way.
1704
Source: New Essays on Human Understanding
I see no necessity that obliges us to affirm that no trace of a perception remains when there is not enough of it to remember having had it.
1704
Source: New Essays on Human Understanding
It is one of my great maxims that it is good to seek demonstrations of the axioms themselves.
1704
Source: New Essays on Human Understanding
To avoid scandals and disorders, regulations can be made [...] by virtue of which it is forbidden to call into question certain established truths: but this is a matter of policy rather than philosophy.
1704
Source: New Essays on Human Understanding
One could not account for the laws of nature without supposing an intelligent cause.
1697
Source: Anagogical Essay in the Search for Causes
The Analysis of the Laws of nature, and the search for causes, leads us to God [...].
1697
Source: Anagogical Essay in the Search for Causes
[...] the ultimate resolution of the Laws of Nature leads us to more sublime principles of order and perfection, which show that the universe is the effect of a universal intelligent power.
1697
Source: Anagogical Essay in the Search for Causes
The knowledge of nature gives birth to art, it gives us many means to preserve life and even provides its conveniences [...].
1697
Source: Anagogical Essay in the Search for Causes
[...] the satisfaction of the mind, which comes from wisdom and virtue, is the greatest pleasure of life; it elevates us to what is eternal, whereas this life is very short.
1697
Source: Anagogical Essay in the Search for Causes
[...] those who seek the Kingdom of God find the rest on their way.
1697
Source: Anagogical Essay in the Search for Causes
[...] the laws of motion [...] have their origin in the wisdom of the author, or in the principle of the greatest perfection, which made him choose them.
1697
Source: Anagogical Essay in the Search for Causes
This true middle ground [...] is that all natural phenomena could be explained mechanically, if we understood them enough; but that the very principles of Mechanics [...] depend on more sublime principles [...].
1697
Source: Anagogical Essay in the Search for Causes
Thus the smallest parts of the universe are regulated according to the order of the greatest perfection; otherwise the whole would not be.
1697
Source: Anagogical Essay in the Search for Causes
[...] there are [...] two Kingdoms in corporeal nature [...] that penetrate each other without confusion [...]: the kingdom of power, according to which everything can be explained mechanically [...] and also the Kingdom of wisdom, according to which everything can be explained [...] by final causes.
1697
Source: Anagogical Essay in the Search for Causes
[...] one can not only say [...] that animals see because they have eyes; but also that eyes were given to them in order to see [...].
1697
Source: Anagogical Essay in the Search for Causes
This principle of nature to act by the most determined ways [...] is, in effect, only architectonic, yet it never fails to observe it.
1697
Source: Anagogical Essay in the Search for Causes
Geometric determinations imply an absolute necessity, the contrary of which implies contradiction, but Architectonic ones only imply a necessity of choice, the contrary of which implies imperfection.
1697
Source: Anagogical Essay in the Search for Causes
One of the most considerable [laws] [...] is the law of continuity [...]. However, it serves not only for examination, but also as a very fertile principle of invention.
1697
Source: Anagogical Essay in the Search for Causes
And nothing seems more effective to me, to prove and admire the sovereign wisdom of the author of things in their very principles.
1697
Source: Anagogical Essay in the Search for Causes
He cannot help but exaggerate everything, like the melancholic, to whom all they see or dream appears black.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I admire the difference between our so-called saints, and people of the world who do not affect the reputation for it, yet possess much more of the reality.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
The meditation of divine things should have made [a man] gentle and charitable; yet what comes from him often seems proud, fierce, and full of harshness.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One must be careful not to irritate a bilious temper. That would take away all the pleasure [...] of a gentle and reasonable discussion.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
He imagines God as a man who makes resolutions according to circumstances; whereas God, foreseeing and ordering all things from all eternity, has chosen from the very first the entire sequence and connection of the universe.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Every man who acts wisely considers all the circumstances and connections of the resolution he makes, and does so according to the measure of his capacity.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is ridiculous to say that this free resolution of God takes away his freedom. Otherwise, to be always free one would have to be always irresolute.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
As soon as one departs ever so slightly from the opinion of certain doctors, they erupt in thunder and lightning.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is to repel people unnecessarily to act in this manner, so that he may henceforth proceed with a little more moderation.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is not permitted to kill souls in order to win others.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
To be always free, must one always be irresolute?
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
God, who sees everything perfectly and in a single glance, can he fail to have made resolutions in conformity with all that he sees?
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is dangerous to engage with such people [...] as soon as one departs ever so slightly from their opinion [...], they erupt in thunder and lightning.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I believe he received my paper when he was in a bad mood, and, finding himself bothered by it, he sought to avenge himself with a repellent answer.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
A diffuse discourse is not a mark of a clear mind, nor a proper means of giving clear ideas to readers.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
A balance is entirely passive, and [...] subject to absolute necessity: whereas the mind not only receives an impression, but also acts, which constitutes the essence of liberty.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
To suppose that when different ways of acting appear equally good, they entirely remove the mind's power to act [...] is to deny that a mind has within itself a principle of action.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
In all animate agents, it is spontaneity; and in intelligent agents, it is properly what we call freedom.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The true and only philosophical question concerning liberty consists in knowing whether the immediate cause or principle [...] of action is really in the one we call the agent.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
It is maintained that space is only the order of coexisting things; yet it is admitted that the material world may be finite; from which it necessarily follows that there must be an empty space beyond the world.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space is not an affection of one or more bodies [...] but it is always, and without variation, the immensity of an immense being, who never ceases to be the same.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Immensity is no less essential to God than His eternity.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
God does not exist in space or in time; but His existence is the cause of space and time.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
A miracle [...] consists simply in the fact that God does it rarely.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The words 'nature' and 'forces of nature,' 'course of nature,' etc., are words that simply mean that a thing happens ordinarily or frequently.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If men were ordinarily to rise from the grave, as wheat grows from seed, we would certainly say that this too was a natural thing.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If pre-established harmony is true, a man sees, hears, and feels nothing, and does not move his body: he only imagines that he sees, hears, feels, and moves his body.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Should an evident quality be called occult, because its immediate cause is perhaps occult, or has not yet been discovered?
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
In the meantime, I cannot help but say that the author reasons in a most extraordinary manner, by comparing gravitation, which is a phenomenon or an actual fact, with the declination of atoms, according to the doctrine of Epicurus.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
A body is never moved naturally except by another body that pushes it by touching it [...]. Any other operation on a body is either miraculous or imaginary.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space, taken as something real and absolute without bodies, would be an eternal, impassible thing, independent of God.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If space is a property [...], this is a strange property [...] which passes from subject to subject. Subjects would thus leave their accidents like a garment, so that other subjects could put it on.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
One has certainly heard it said that the property is in the subject; but one has never heard it said that the subject is in its property.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Infinite space is not the immensity of God; finite space is not the extension of bodies, just as time is not duration.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space is that which results from places taken together. [...] this can only be ideal, containing a certain order in which the mind conceives the application of relations.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The principle of sufficient reason alone makes all these phantoms of the imagination disappear. Men easily create fictions for want of properly using this great principle.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Of time, only instants ever exist, and an instant is not even a part of time. [...] Time can only be an ideal thing.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Motion is independent of observation, but [...] it is not independent of observability. There is no motion when there is no observable change.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
I do not say that matter and space are the same thing; I only say that there is no space where there is no matter; and that space in itself is not an absolute reality.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
God never makes a resolution about the ends without at the same time making one about the means and all the circumstances.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
God can do everything that is possible, but He only wants to do what is best.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
It is a misfortune of men to finally become disgusted with reason itself, and to grow weary of the light. Chimeras begin to return and are pleasing, because they have something of the marvelous.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The principle of the need for a sufficient reason for a thing to exist, for an event to happen, for a truth to obtain. Is this a principle that needs proof?
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Everything that happens in the body of a man, and of any animal, is as mechanical as what happens in a watch. The difference is only that which must exist between a machine of divine invention and the product of a limited craftsman.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The best course is not always the one that tends to avoid evil, since it may be that evil is accompanied by a greater good.
1710
Source: Theodicy
An imperfection in the part may be required for a greater perfection in the whole.
1710
Source: Theodicy
A world with evil could be better than a world without evil.
1710
Source: Theodicy
Good can and does go to infinity, whereas evil has its limits.
1710
Source: Theodicy
The little evil that exists is required for the consummation of the immense good found therein.
1710
Source: Theodicy
Causes incline the will, without necessitating it.
1710
Source: Theodicy
Although one is never in a perfect indifference of equilibrium [...] there is always a prevailing inclination, [but] it never renders the resolution absolutely necessary.
1710
Source: Theodicy
One does not will these evils, but one is willing to permit them for a greater good, which one cannot reasonably refrain from preferring.
1710
Source: Theodicy
All purely positive, or absolute, reality is a perfection; and imperfection comes from limitation, that is, from the privative.
1710
Source: Theodicy
Limitations or privations result from the original imperfection of creatures, which limits their receptivity.
1710
Source: Theodicy
Some disorders in the parts [...] marvellously enhance the beauty of the whole, just as certain dissonances, properly used, make the harmony more beautiful.
1710
Source: Theodicy
There is nothing less servile than to be always led to the good, and always by one's own inclination, without any constraint and without any displeasure.
1710
Source: Theodicy
It is the true and most perfect freedom to be able to make the best use of one's free will.
1710
Source: Theodicy
For the wise, 'necessary' and 'ought' are equivalent things.
1710
Source: Theodicy
A will that would always let itself be guided by chance would be scarcely better for the government of the universe than the fortuitous concourse of corpuscles.
1710
Source: Theodicy
It is true [...] that there are [...] people who even deny natural religion, or who corrupt it extremely; but [...] this must be attributed mainly to the false philosophy of the materialists.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[The mathematical principles] are the only principles that prove that matter is the smallest and least considerable part of the universe.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
God, being present everywhere, perceives things by His immediate presence, in all the space where they are, without the intervention or help of any organ or means.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
God sees everything by His immediate presence, being actually present to the things themselves, to all the things that are in the universe.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The skill of all human craftsmen consists only in composing and joining certain parts, which have a motion whose principles are entirely independent of the craftsman.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
It is quite different with regard to God, who not only composes and arranges things, but is also the author of their primitive powers [...] and perpetually preserves them.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
To say that nothing is done without His providence and His inspection is not to debase His work, but rather to make known its greatness and excellence.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The idea that the world is a great machine that moves without God's intervention [...] introduces materialism and fatalism.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[This idea], under the pretext of making God a Supramundane Intelligence, effectively tends to banish providence and God's government from the world.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
For the same reason that a philosopher can imagine that everything in the world happens [...] without Providence having any part in it, it will not be difficult for a Pyrrhonian to push the reasoning further, and to suppose that things have gone on from all eternity.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If a king had a kingdom where everything happened without his intervention [...] it would be a kingdom in name only for him; and he would not deserve to have the title of king or governor.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Those who maintain that the universe does not need God to direct and govern it continually advance a doctrine that tends to banish Him from the world.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
A balance is not an agent: it is entirely passive [...] But intelligent beings are agents; they are not merely passive, and motives do not act upon them as weights act upon a balance.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Although two things may be perfectly similar, they do not cease to be two things.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The parts of time are as perfectly similar as those of space, and yet two instants are not the same instant.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space is not contained between bodies; but bodies, being in immense space, are themselves bounded by their own dimensions.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Empty space is not an attribute without a subject; for by this space we do not mean a space where there is nothing, but a space without bodies.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space is not a substance, but an attribute [...]. Space is immense, immutable, and eternal; and the same must be said of duration.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
There can be real motion where there is no relative motion; and there can be relative motion where there is no real motion.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Space and time are quantities; which cannot be said of situation and order.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If the soul did not act upon the body, and if the body [...] yet conformed to the soul's will [...], it would be a perpetual miracle.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
All action consists in giving a new force to the things upon which it is exerted. Without this, it would not be a real action, but a mere passion.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Time is not the order of things that succeed one another [...] for they can succeed one another faster or slower in the same order of succession, but not in the same time.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
The idea of a miracle necessarily includes the idea of something rare and extraordinary. [...] [Natural things] are not miracles, because they are common things.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If one body were to attract another without the intervention of any means, it would not be a miracle, but a contradiction; for it would be to suppose that a thing acts where it is not.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If God places a cube of matter behind another equal cube [...], this choice is not unworthy of God's perfection, although these two situations are perfectly similar.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If there are no perfectly solid parts in matter, there is no matter in the universe; [...] it will follow that bodies are composed solely of pores [...].
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
I am not one of those for whom commitment takes the place of reason.
1695
Source: Explanation of the New System of the Communication of Substances
The unity of a clock [...] is entirely different from that of an animal: [...] a clock is nothing other than an assemblage.
1695
Source: Explanation of the New System of the Communication of Substances
There is no useless substance; they all contribute to the design of God.
1695
Source: Explanation of the New System of the Communication of Substances
When a thing cannot fail to be, it is not necessary, in order to accept it, to ask what purpose it can serve.
1695
Source: Explanation of the New System of the Communication of Substances
What purpose does the incommensurability of the side with the diagonal serve?
1695
Source: Explanation of the New System of the Communication of Substances
God willed that there be more rather than fewer substances, and He found it good that these modifications of the soul should correspond to something outside.
1695
Source: Explanation of the New System of the Communication of Substances
It is very true to say that substances act upon one another, provided one understands that one is the cause of changes in the other as a consequence of the laws of harmony.
1695
Source: Explanation of the New System of the Communication of Substances
I know nothing of these vain, useless, and inactive masses [...]. There is action everywhere [...] I believe there is no body without motion, nor any substance without effort.
1695
Source: Explanation of the New System of the Communication of Substances
All hypotheses are made expressly, and all systems come after the fact, to save the phenomena or appearances.
1695
Source: Explanation of the New System of the Communication of Substances
It is commonly sufficient that a hypothesis is found a posteriori, because it satisfies the phenomena; but when one also has reasons for it a priori, so much the better.
1695
Source: Explanation of the New System of the Communication of Substances
I love truth, and if I were so fond of novelties, I would be more eager to produce them.
1695
Source: Explanation of the New System of the Communication of Substances
There are, in my view, efforts in all substances; but these efforts are properly only within the substance itself.
1695
Source: Explanation of the New System of the Communication of Substances
I strongly approve of seeking to demonstrate truths from first principles: this is more useful than one might think.
1695
Source: Explanation of the New System of the Communication of Substances
[...] as if this exact correspondence that substances have among themselves through their own proper laws [...] were not a thing admirably beautiful in itself and worthy of its author.
1695
Source: Explanation of the New System of the Communication of Substances
[My system] conserves force and direction, and in a word all the natural laws of bodies, notwithstanding the changes that occur in them as a consequence of those of the soul.
1695
Source: Explanation of the New System of the Communication of Substances
It is always necessary that, besides the difference of time and place, there be an internal principle of distinction [...]. The specifics of identity and diversity, therefore, do not consist in time and place.
1704
Source: New Essays on Human Understanding
If two individuals were perfectly similar [...] and indistinguishable in themselves, there would be no principle of individuation; and I would even dare to say that there would be no individual distinction [...] under this condition.
1704
Source: New Essays on Human Understanding
A great princess [...] once said [...] that she did not believe there were two perfectly identical leaves. A witty gentleman [...] was convinced by his own eyes that a difference could always be noticed.
1704
Source: New Essays on Human Understanding
Organized bodies [...] remain the same only in appearance, and not, strictly speaking. It is much like a river that is always changing its water, or like the ship of Theseus that the Athenians were always repairing.
1704
Source: New Essays on Human Understanding
Instead of a transmigration of the soul, there is transformation, envelopment or development, and finally a flux of the body of that soul.
1704
Source: New Essays on Human Understanding
The identity of substance would be there; but if there were no connection of remembrance [...] there would not be enough moral identity to say that it would be the same person.
1704
Source: New Essays on Human Understanding
The word 'person' implies a thinking, intelligent being, capable of reason and reflection, who can consider itself as the same [...] at different times and in different places.
1704
Source: New Essays on Human Understanding
Consciousness, or the feeling of the self, proves a moral or personal identity.
1704
Source: New Essays on Human Understanding
I would not say that I am not the self who was in the cradle, on the pretext that I no longer remember anything [...]. It is sufficient [...] that there be a connecting link of consciousness from one state to another.
1704
Source: New Essays on Human Understanding
The self makes for the real and physical identity, and the appearance of the self, accompanied by truth, adds personal identity to it.
1704
Source: New Essays on Human Understanding
An immaterial being or a spirit cannot be stripped of all perception of its past existence. It retains impressions of everything that has ever happened to it, but these feelings are most often too small to be distinguishable.
1704
Source: New Essays on Human Understanding
Present or immediate memory, or [...] the consciousness or reflection which accompanies the internal action, cannot naturally deceive; otherwise one would not even be certain that one is thinking of such or such a thing.
1704
Source: New Essays on Human Understanding
Human laws do not punish the madman for the actions of the sane man, nor the sane man for what the madman has done: whereby they make them two persons.
1704
Source: New Essays on Human Understanding
On the great and dreadful day of judgment [...] one has the right to believe that no one will have to answer for what is entirely unknown to them, and that each will receive their due, being accused by their own conscience.
1704
Source: New Essays on Human Understanding
The question of whether the same man remains is a question of name, depending on whether one understands by 'man' only the rational spirit, or only the body [...], or finally the spirit united to such a body.
1704
Source: New Essays on Human Understanding
There is only a matter of more or less, which changes nothing in the realm of possibilities.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
To not see its possibility would be to not sufficiently consider the degrees of things.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
The universal marvelousness causes the particular marvelousness to cease and absorbs it, so to speak, since it accounts for it.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
[...] the smallest body receives some impression from the slightest change in all others, however distant and small they may be, and must thus be an exact mirror of the universe.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
Everything happens in the soul as if there were no body; just as [...] everything happens in the body as if there were no soul.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
What is good in the hypotheses of Epicurus and Plato, of the greatest materialists and the greatest idealists, is united here.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
One transfers admiration from the work to the inventor, just as when we now see that the planets do not need to be guided by intelligences.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
They are worlds in miniature, [...] fruitful simplicities; unities of substance, but virtually infinite, through the multitude of their modifications.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
[...] the present is big with the future.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
The most abstract thoughts require some imagination.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
Extension is the order of possible coexistences, as time is the order of inconstant possibilities [...].
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
Things could not be made intelligible except by these rules, alone capable, along with those of harmony, [...] of allowing us to enter into the reasons and views of the author of things.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
It will not be proof of impossibility to say merely that one cannot conceive of such and such a thing, when one does not point out how it offends reason [...].
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
God practices geometry, and [...] mathematics are a part of the intellectual world, and are the most suited to provide entry to it.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
Men have never shown more wit than when they have been jesting.
1702
Source: Reply to the reflections contained in the second edition of Mr. Bayle's Critical Dictionary, article Rorarius on the system of pre-established harmony
Reason is the known truth whose connection with another, less known truth, makes us give our assent to the latter.
1704
Source: New Essays on Human Understanding
Men [...] rise above beasts, in that they see the connections of truths; connections [...] which themselves constitute necessary and universal truths.
1704
Source: New Essays on Human Understanding
God, having made man a two-legged creature, left it to Aristotle to make him a rational animal.
1704
Source: New Essays on Human Understanding
Why is it that men never make syllogisms to themselves when they are seeking the truth or teaching it to those who sincerely desire to know it?
1704
Source: New Essays on Human Understanding
I hold that the invention of the form of syllogisms is one of the most beautiful [...] of the human mind. It is a kind of universal mathematics whose importance is not sufficiently known.
1704
Source: New Essays on Human Understanding
The laws of logic [...] are nothing other than those of common sense put in order and in writing.
1704
Source: New Essays on Human Understanding
It will not be the imitators who, like cattle, follow the beaten path.
1704
Source: New Essays on Human Understanding
God alone has the advantage of having only intuitive knowledge. [...] [Higher beings] must also find difficulties in their path, without which they would not have the pleasure of making discoveries, which is one of the greatest.
1704
Source: New Essays on Human Understanding
The foundation is everywhere the same, which is a fundamental maxim of mine and which reigns throughout my philosophy.
1704
Source: New Essays on Human Understanding
The argumentum ad ignorantiam is good in cases of presumption where it is reasonable to hold to an opinion until the contrary is proven.
1704
Source: New Essays on Human Understanding
One must distinguish between what is necessary to support our knowledge, and what serves as the foundation for our received doctrines or our practices.
1704
Source: New Essays on Human Understanding
The way of speaking that opposes reason to faith, although much authorized, is improper; for it is by reason that we must believe.
1704
Source: New Essays on Human Understanding
He who believes without having any reason to believe may be in love with his own fancies, but it is not true that he seeks the truth.
1704
Source: New Essays on Human Understanding
I want faith to be founded on reason: without that, why would we prefer the Bible to the Quran or the ancient books of the Brahmins?
1704
Source: New Essays on Human Understanding
Men judge things only according to their experience, which is extremely limited, and everything that does not conform to it seems an absurdity to them.
1704
Source: New Essays on Human Understanding
It seems to me that natural religion itself is weakening extremely.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
Many make souls corporeal, others make God himself corporeal.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[Some] at least doubt whether souls are not material and naturally perishable.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[Some say] that space is the organ which God uses to sense things.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
If He [God] needs some means to sense things, then they do not depend entirely on Him and are not His production.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
According to [some], God needs to wind up his watch from time to time, otherwise it would cease to work.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
He [God] did not have enough foresight to make it a perpetual motion.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
This machine of God is even so imperfect [...] that He is obliged to mend it, like a watchmaker his work.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
[The craftsman] will be all the worse a master, the more often he is obliged to touch up and correct [his work].
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
In my opinion, the same force and vigor always subsists in it, and only passes from matter to matter, according to the laws of nature, and the beautiful pre-established order.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
I hold that when God performs miracles, it is not to supply the needs of nature, but those of grace.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
To judge otherwise would be to have a very low idea of the wisdom and power of God.
1715-1716
Source: Collection of letters between Leibniz and Clarke (Félix Alcan)
That which contains in its idea all perfections [...] also includes existence in its essence, since existence is one of the perfections.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
I hold a middle ground between those who take this reasoning for a sophism and [...] who take it for a completed demonstration.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
It is a demonstration, but an imperfect one, which requires or presupposes a truth that still deserves to be demonstrated.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
One cannot reason perfectly about ideas without knowing their possibility.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
Every being must be held to be possible until its impossibility is proven.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
A simpler demonstration could be formed, without speaking of perfections, so as not to be stopped by those who deny that all perfections are compatible.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
God is a being [...] who exists by his essence, [...] it is easy to conclude from this definition that such a being, if it is possible, exists.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
The essence of a thing is but that which constitutes its possibility [...], it is quite manifest that to exist by one's essence is to exist by one's possibility.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
A modal proposition, which would be one of the best fruits of all logic: if the necessary being is possible, it exists.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
The necessary being and the being by its essence are but one and the same thing.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
Those who maintain that from mere possible notions, ideas, or essences one can never infer actual existence [...] deny the possibility of the self-existent being.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
If the self-existent being is impossible, all beings through another are also impossible; since they ultimately exist only through the self-existent being; thus nothing could exist.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
If the necessary being is not, there is no possible being.
Late 17th - early 18th century
Source: On the Cartesian demonstration of the existence of God by R. P. Lami
Although only particular things exist, most words are nonetheless general terms.
1704
Source: New Essays on Human Understanding
The main purpose of language is to excite in the mind of my listener an idea similar to my own.
1704
Source: New Essays on Human Understanding
I would dare to say that almost all words are originally general terms, because it will very rarely happen that a name is invented expressly without reason to mark a specific individual.
1704
Source: New Essays on Human Understanding
It is impossible for us to have knowledge of individuals and to find the means to precisely determine the individuality of any thing, unless we keep the thing itself.
1704
Source: New Essays on Human Understanding
Individuality encompasses the infinite, and only one who is capable of comprehending it can have knowledge of the principle of individuation.
1704
Source: New Essays on Human Understanding
The art of arranging things into genera and species is of no small importance and greatly serves both judgment and memory.
1704
Source: New Essays on Human Understanding
Generality consists in the resemblance of singular things to one another, and this resemblance is a reality.
1704
Source: New Essays on Human Understanding
If men differ in the name, does that change the things or their resemblances?
1704
Source: New Essays on Human Understanding
Whether men join this or that idea or not [...] makes no difference to essences, genera, or species, since it is only a matter of possibilities, which are independent of our thought.
1704
Source: New Essays on Human Understanding
Essence, in the end, is nothing other than the possibility of what is proposed.
1704
Source: New Essays on Human Understanding
It does not depend on us to join ideas as we see fit, unless that combination is justified either by reason, which shows it to be possible, or by experience, which shows it to be actual [...].
1704
Source: New Essays on Human Understanding
There is only one essence of a thing, but there are several definitions that express the same essence, just as the same structure [...] can be represented by different scenographies [...].
1704
Source: New Essays on Human Understanding
The real definition [...] shows the possibility of the defined, and the nominal one does not.
1704
Source: New Essays on Human Understanding
Essences are perpetual, because they are only concerned with what is possible.
1704
Source: New Essays on Human Understanding
The individual notion of a substance encompasses everything that must ever happen to it, and this is what distinguishes accomplished beings from those that are not.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Since our thoughts are but consequences of the nature of our soul [...], it is useless to ask for the influence of another particular substance, besides the fact that this influence is absolutely inexplicable.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Each substance expresses the entire universe in its own way.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Action is attributed to that substance whose expression is more distinct, and it is called the cause.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
All motion in itself is merely a relative thing, namely: a change of position which cannot be attributed to a specific subject with mathematical precision.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
The agreement of all phenomena of different substances comes only from the fact that they are all productions of the same cause, namely God.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
We do nothing but think, [...] we procure for ourselves only thoughts, and phenomena are only thoughts.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
God initially created all substances in such a way that thereafter all their phenomena correspond to one another, without needing a mutual physical influence for that.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Souls change nothing in the order of bodies, nor bodies in that of souls. [...] One particular substance has no physical influence on another.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One must attribute the action to the substance whose expression is more distinct, especially as this is sufficient in practice for procuring phenomena.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One would have to be certain that bodies are substances and not merely true phenomena like the rainbow.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
One will never find a body of which one can say that it is truly a substance. It will always be an aggregate of several [...], beings by aggregation having only as much reality as there is in their ingredients.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Extension is an attribute that cannot constitute a complete being, [...] it expresses only a present state, but in no way the future and the past, as the notion of a substance must.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
Although the consideration of forms or souls is useless in particular physics, it is nonetheless important in metaphysics.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
The more one is enlightened and informed about the works of God, the more one will be disposed to find them excellent and entirely satisfying to all that one could have wished for.
1686
Source: Discourse on Metaphysics
By saying that things are not good by any rule of goodness, but by the sole will of God, one destroys, it seems to me, without thinking, all love for God and all his glory.
1686
Source: Discourse on Metaphysics
To believe that God acts in some matter without having any reason for His will [...] is a sentiment little conformed to His glory.
1686
Source: Discourse on Metaphysics
One must not be a quietist nor wait ridiculously with folded arms for what God will do, [...] but one must act according to the presumptive will of God, [...] striving with all our power to contribute to the general good.
1686
Source: Discourse on Metaphysics
The simplicity of God's ways [...] properly applies to the means, while on the contrary, variety, richness, or abundance applies to the ends or effects.
1686
Source: Discourse on Metaphysics
God has chosen [the world] that is the most perfect, that is to say, that which is at the same time the simplest in hypotheses and the richest in phenomena.
1686
Source: Discourse on Metaphysics
The nature of an individual substance or of a complete being is to have a notion so complete that it is sufficient to contain and to have deduced from it all the predicates of the subject to which this notion is attributed.
1686
Source: Discourse on Metaphysics
Every substance is like a whole world and like a mirror of God or of the whole universe, which each one expresses in its own way, much as the same city is represented differently according to the different positions of the one who looks at it.
1686
Source: Discourse on Metaphysics
A distinction must be made between what is certain and what is necessary: [...] future contingents are assured, since God foresees them, but it is not for that reason admitted that they are necessary.
1686
Source: Discourse on Metaphysics
Each substance is like a world apart, independent of every other thing but God; thus all our phenomena [...] are but consequences of our own being.
1686
Source: Discourse on Metaphysics
It is unreasonable to introduce a sovereign intelligence ordering things, and then, instead of employing its wisdom, to use only the properties of matter to explain the phenomena.
1686
Source: Discourse on Metaphysics
The true cause is one thing... and that which is only a condition, without which the cause could not be a cause, is another.
1686
Source: Discourse on Metaphysics
Nothing enters our mind from the outside, and it is a bad habit we have of thinking as if our soul received some messenger species and as if it had doors and windows.
1686
Source: Discourse on Metaphysics
The soul should often think as if there were only God and it in the world.
1686
Source: Discourse on Metaphysics
The immortality sought in morality and religion does not consist in this perpetual subsistence alone [...] for, without the memory of what one has been, it would have nothing desirable.
1686
Source: Discourse on Metaphysics
He has very strange opinions in physics, which hardly seem sustainable.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I tried to tell him my thoughts in a way that would not offend him.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It would be much better if he were to abandon, at least for some time, these kinds of speculations...
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
...to apply oneself to the greatest matter one can have, which is the choice of the true religion.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
It is much to be feared that death will surprise him, unless he has made a resolution so important for his salvation.
1686
Source: Correspondence of Leibniz and Arnauld (Félix Alcan)
I see very well [...] that my thought [...] needs clarification.
1696
Source: Second Clarification of the System of Communication of Substances
How could I prove what I have advanced concerning the harmony of two substances as different as the soul and the body.
1696
Source: Second Clarification of the System of Communication of Substances
Imagine two clocks or watches that are in perfect agreement.
1696
Source: Second Clarification of the System of Communication of Substances
The first [way] consists in a mutual influence; the second is to assign a skilled craftsman to them who adjusts them [...] at all times; the third is to manufacture them with such art and precision that one can be assured of their agreement.
1696
Source: Second Clarification of the System of Communication of Substances
Now, put the soul and the body in the place of these two clocks.
1696
Source: Second Clarification of the System of Communication of Substances
The way of influence is that of common philosophy; but, as one cannot conceive of material particles that could pass from one of these substances to the other, this view must be abandoned.
1696
Source: Second Clarification of the System of Communication of Substances
The way of the Creator's continual assistance [...] is to bring in a Deus ex machina in a natural and ordinary matter.
1696
Source: Second Clarification of the System of Communication of Substances
Thus, only my hypothesis remains, that is, the way of harmony.
1696
Source: Second Clarification of the System of Communication of Substances
God has made from the beginning each of these two substances of such a nature that by following only its own laws [...], it nevertheless agrees with the other.
1696
Source: Second Clarification of the System of Communication of Substances
[Each substance] agrees with the other, just as if there were a mutual influence, or as if God always had a hand in it.
1696
Source: Second Clarification of the System of Communication of Substances
I need not prove anything, unless one demands that I prove that God is skillful enough to use this preemptive artifice.
1696
Source: Second Clarification of the System of Communication of Substances
You see clearly that this way is the most beautiful and the most worthy of Him [God].
1696
Source: Second Clarification of the System of Communication of Substances
You suspected that my explanation would be contrary to the very different idea we have of mind and body; but [...] no one has better established their independence.
1696
Source: Second Clarification of the System of Communication of Substances
While one has been obliged to explain their communication by a sort of miracle, one has always given reason to fear that the distinction between the body and the soul was not as real as is believed.
1696
Source: Second Clarification of the System of Communication of Substances
I will not be sorry to sound out enlightened people on the thoughts I have just explained to you.
1696
Source: Second Clarification of the System of Communication of Substances
Knowledge is intuitive when the mind perceives the agreement of two ideas immediately by themselves without the intervention of any other.
1704
Source: New Essays on Human Understanding
Whoever asks for a greater certainty does not know what he is asking for.
1704
Source: New Essays on Human Understanding
Truths of reason are necessary and truths of fact are contingent.
1704
Source: New Essays on Human Understanding
All primitive truths of reason or of fact have this in common, that they cannot be proven by anything more certain.
1704
Source: New Essays on Human Understanding
[...] one must not despise any truth.
1704
Source: New Essays on Human Understanding
Thus the Cartesian principle [I think, therefore I am] is good, but it is not the only one of its kind.
1704
Source: New Essays on Human Understanding
The image reflected by several mirrors [...], weakens more and more with each reflection [...]. It is the same with knowledge produced by a long series of proofs.
1704
Source: New Essays on Human Understanding
It is much more difficult to find important truths [...] than to find the demonstration of truths that another has discovered.
1704
Source: New Essays on Human Understanding
One often arrives at beautiful truths through synthesis, by going from the simple to the complex.
1704
Source: New Essays on Human Understanding
[...] it is perhaps for lack of application on our part that mathematics alone has achieved demonstrations.
1704
Source: New Essays on Human Understanding
Opinion, founded in the probable, also perhaps deserves the name of knowledge; otherwise almost all historical knowledge and much else will fall.
1704
Source: New Essays on Human Understanding
The study of the degrees of probability would be very important and is still lacking, and this is a great defect in our logics.
1704
Source: New Essays on Human Understanding
The true criterion in the matter of the objects of the senses is the connection of phenomena [...].
1704
Source: New Essays on Human Understanding
It is not impossible, metaphysically speaking, that there could be a dream as continuous and lasting as a man's life; but this is a thing as contrary to reason as the fiction of a book being formed by chance [...].
1704
Source: New Essays on Human Understanding
[...] as long as the phenomena are connected, it does not matter whether we call them dreams or not, since experience shows that we are not mistaken in the measures we take based on phenomena [...].
1704
Source: New Essays on Human Understanding