Ce grand ouvrage, toujours plus merveilleux à mesure qu’il est plus connu, nous donne une si grande idée de son ouvrier, que nous en sentons notre esprit accablé d’admiration et de respect.
[The Universe] This great work, always more amazing in proportion as it is better known, raises in us so grand an idea of its Maker, that we find our mind overwhelmed with feelings of wonder and adoration.

L’astronomie est fille de l’oisiveté, la géométrie est fille de l’intérêt
Astronomy is the daughter of idleness, geometry is the daughter of interest.

La nature veut que dans certains temps les hommes se succèdent les uns aux autres par le moyen de la mort; il leur est permis de se défendre contr’elle jusqu’à un certain point; mais passé cela, on aura beau faire de nouvelles découvertes dans l’Anatomie, on aura beau pénétrer de plus en plus dans les secrets de la structure du corps humain, on ne prendra point la Nature pour dupe, on mourra comme à l’ordinaire.
Nature intends that at fixed periods men should succeed each other by the instrumentality of death. They are allowed to keep it at bay up to a certain point; but when that is passed, it will be of no use to make new discoveries in anatomy, or to penetrate more and more into the secrets of the structure of the human body; we shall never outwit nature, we shall die as usual.

Notre folie à nous autres est de croire aussi que toute la nature, sans exception, est destinée à nos usages.
We, too, are silly enough to believe that all nature is intended for our benefit.

Nous avons l’obligation aux Anciens de nous avoir épuisé la plus grande partie des idées fausses qu’on le pouvait faire
We are under obligation to the ancients for having exhausted all the false theories that could be formed.

Quand on demande à nos philosophes à quoi sert ce nombre prodigieux d’étoiles fixes, dont une partie suffirait pour faire ce qu’elles font toutes, ils vous répondent froidement qu’elles servent à leur réjouir la vue.
When our philosophers are asked what is the use of these countless myriads of fixed stars, of which a small part would be sufficient to do what they all do, they coolly tell us that they are made to give delight to their eyes.

Quelquefois, par exemple, je me figure que je suis suspendu en l’air, et que j’y demeure sans mouvement, pendant que la Terre tourne sous moi en vingt-quatre heures. Je vois passer sous mes yeux tous ces visages différents, les uns blancs, les autres noirs, les autres basanés, les autres olivâtres. D’abord ce sont des chapeaux et puis des turbans, et puis des têtes chevelues, et puis des têtes rasées; tantôt des villes à clochers, tantôt des villes à longues aiguilles qui ont des croissants, tantôt des villes à tours de porcelaine, tantôt de grands pays qui n’ont que des cabanes; ici de vastes mers, là des déserts épouvantables; enfin, toute cette variété infinie qui est sur la surface de la Terre.
Sometimes, for instance, I imagine that I am suspended in the air, and remain there motionless, while the earth turns under me in four-and-twenty hours. I see pass beneath me all these different countenances, some white, others black, others tawny, others olive-colored. At first they wear hats, and then turbans, then heads with long hair, then heads shaven; sometimes towns with steeples, sometimes towns with long spires, which have crescents, sometimes towns with porcelain towers, sometimes extensive countries that have only huts; here wide seas; there frightful deserts; in short, all this infinite variety on the surface of the earth.

Surtout l’astronomie et l’anatomie sont les deux sciences qui nous offrent le plus sensiblement deux grands caractères du Créateur; l’une, son immensité, par les distances, la grandeur, et le nombre des corps célestes; l’autre, son intelligence infinie, par la méchanique des animaux.
Above all, astronomy and anatomy are the two sciences which present to our minds most significantly the two grand characteristics of the Creator; the one, His immensity, by the distances, size, and number of the heavenly bodies; the other, His infinite intelligence, by the mechanism of animate beings.

~~[Orphan]~~ Mathematicians are like lovers. Grant a mathematician the least principle, and he will draw from it a consequence which you must also grant him, and from this consequence another.

A work of morality, politics, criticism will be more elegant, other things being equal, if it is shaped by the hand of geometry.

Behold a universe so immense that I am lost in it. I no longer know where I am. I am just nothing at all. Our world is terrifying in its insignificance.

Following the example of Archimedes who wished his tomb decorated with his most beautiful discovery in geometry and ordered it inscribed with a cylinder circumscribed by a sphere, James Bernoulli requested that his tomb be inscribed with his logarithmic spiral together with the words, “Eadem mutata resurgo,” a happy allusion to the hope of the Christians, which is in a way symbolized by the properties of that curve.

It is the destiny of the sciences, which must necessarily be in the hands of a few, that the utility of their progress should be invisible to the greater part of mankind, especially if those sciences are associated with unobtrusive pursuits. Let a greater facility in using our navigable waters and opening new lines of communication but once exist, simply because at present we know vastly better how to level the ground and construct locks and flood-gates—what does it amount to? The workmen have had their labors lightened, but they themselves have not the least idea of the skill of the geometer who directed them; they have been put in motion nearly as the body is by a soul of which it knows nothing; the rest of the world has even less perception of the genius which presided over the enterprise, and enjoys the success it has attained only with a species of ingratitude.

Leibniz never married; he had considered it at the age of fifty; but the person he had in mind asked for time to reflect. This gave Leibniz time to reflect, too, and so he never married.

Let us be well assured of the Matter of Fact, before we trouble our selves with enquiring into the Cause. It is true, that this Method is too slow for the greatest part of Mankind, who run naturally to the Cause, and pass over the Truth of the Matter of Fact.

Nature is never so admired as when she is understood.

Since the princes take the Earth for their own, it’s fair that the philosophers reserve the sky for themselves and rule there, but they should never permit the entry of others.

The art of flying has only just been born; it will be perfected, and some day we’ll go to the Moon.

The calculus is to mathematics no more than what experiment is to physics, and all the truths produced solely by the calculus can be treated as truths of experiment. The sciences must proceed to first causes, above all mathematics where one cannot assume, as in physics, principles that are unknown to us. For there is in mathematics, so to speak, only what we have placed there… If, however, mathematics always has some essential obscurity that one cannot dissipate, it will lie, uniquely, I think, in the direction of the infinite; it is in that direction that mathematics touches on physics, on the innermost nature of bodies about which we know little….

They will have the World to be in Large, what a Watch is in Small; which is very regular, and depends only upon the just disposing of the several Parts of the Movement.

To what purpose should People become fond of the Mathematicks and Natural Philosophy? … People very readily call Useless what they do not understand. It is a sort of Revenge… One would think at first that if the Mathematicks were to be confin’d to what is useful in them, they ought only to be improv'd in those things which have an immediate and sensible Affinity with Arts, and the rest ought to be neglected as a Vain Theory. But this would be a very wrong Notion. As for Instance, the Art of Navigation hath a necessary Connection with Astronomy, and Astronomy can never be too much improv'd for the Benefit of Navigation. Astronomy cannot be without Optics by reason of Perspective Glasses: and both, as all parts of the Mathematicks are grounded upon Geometry … .

When the Heavens were a little blue Arch, stuck with Stars, methought the Universe was too straight and close: I was almost stifled for want of Air: but now it is enlarged in height and breadth, and a thousand Vortex’s taken in. I begin to breathe with more freedom, and I think the Universe to be incomparably more magnificent than it was before.

You say Beasts are Machines like Watches? But put the Machine called a Dog, and the Machine called a Bitch to one another for some time, and there may result another little Machine; whereas two Watches might be together all their Life-time, without ever producing a third Watch. Now Madam de B— and I think, according to our Philosophy, that all things which being but two, are endued with the Virtue of making themselves three, are of a much higher Nature than a Machine.