“I hold that it is only when we can prove everything we assert that we understand perfectly the thing under consideration.”

Our reasonings are grounded upon two great principles, that of contradiction, in virtue of which we judge false that which involves a contradiction, and true that which is opposed or contradictory to the false.

The larger the mass of collected things, the less will be their usefulness. Therefore, one should not only strive to assemble new goods from everywhere, but one must endeavor to put in the right order those that one already possesses.

Take what you need, do what you should, you will get what you want.

Of what use would it be to you, sir, to become King of China on condition that you forgot what you have been? Would it not be the same as if God, at the same time he destroyed you, created a King in China?

I have said more than once, that I hold space to be something purely relative, as time; an order of coexistences, as time is an order of successions.

A distinction must be made between true and false ideas, and that too much rein must not be given to a man’s imagination under pretext of its being a clear and distinct intellection.

He who understands Archimedes and Apollonius will admire less the achievements of the foremost men of later times.

Music is the pleasure the human mind experiences from counting without being aware that it is counting.

I hold that the mark of a genuine idea is that its possibility can be proved, either a priori by conceiving its cause or reason, or a posteriori when experience teaches us that it is in fact in nature.

We may say, that not only the soul (the mirror of an indestructible universe) is indestructible, but also the animal itself is, although its mechanism is frequently destroyed in parts.

There never is absolute birth nor complete death, in the strict sense, consisting in the separation of the soul from the body. What we call births are developments and growths, while what we call deaths are envelopments and diminutions.

Nothing is more important than to see the sources of invention which are, in my opinion more interesting than the inventions themselves.

Justice is charity in accordance with wisdom.

I also readily admit that there are animals, taken in the ordinary sense, that are incomparably larger than those we know of, and I have sometimes said in jest that there might be a system like ours which is the pocketwatch of some enormous giant.

To love is to be delighted by the happiness of someone, or to experience pleasure upon the happiness of another. I define this as true love.

Either there are no corporeal substances, and bodies are merely phenomena which are true or consistent with each other, such as a rainbow or a perfectly coherent dream, or there is in all corporeal substances something analogous to the soul.

When faith lays hold, impossibilities must yield.

The aim of every artist is to arrest motion, which is life, by artificial means and hold it fixed so that a hundred years later, when a stranger looks at it, it moves again since it is life.

Yes. A man will talk about how he’d like to escape from living folks. But it’s the dead folks that do him the damage. It’s the dead ones that lay quiet in one place and dont try to hold him, that he cant escape from.

I want him to hold what he has earned and got. I have all the rank I want.

If for the sake of a crowded audience you do wish to hold a lecture, your ambition is no laudable one, and at least avoid all citations from the poets, for to quote them argues feeble industry.

Human beings seem to hold on more tenaciously to a cultural identity that is learned through suffering than to one that has been acquired through pleasure and delight.

My today’s self perpetually slips out of any hold of it that I may try to take.

President Joe Biden is unfit to hold the office of the Presidency. His pattern of abuse of power as President Obama’s Vice President is lengthy and disturbing.