“Every present state of a simple substance is the natural consequence of its preceding state, in such a way that its present is big with its future.”

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.

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

I do not conceive of any reality at all as without genuine unity.

Nature does not make leaps.

Taking mathematics from the beginning of the world to the time when Newton lived, what he had done was much the better half.

Nothing is necessitated whose opposite is possible.

Every substance is as a world apart, independent of everything else except God.

We never have a full demonstration, although there is always an underlying reason for the truth, even if it is only perfectly understood by God, who alone penetrated the infinite series in one stroke of the mind.

The present is big with the future, the future might be read in the past, the distant is expressed in the near.

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

In my judgment an organic machine new to nature never arises, since it always contains an infinity of organs so that it can express, in its own way, the whole universe; indeed, it always contains all past and present times.

But it is the knowledge of necessary and eternal truths which distinguishes us from mere animals, and gives us reason and the sciences, raising us to knowledge of ourselves and God. It is this in us which we call the rational soul or mind.

A great doctor kills more people than a great general.

The most perfect society is that whose purpose is the universal and supreme happiness.

Philosophy consists mostly of kicking up a lot of dust and then complaining that you can’t see anything.

Imaginary numbers are a fine and wonderful refuge of the divine spirit almost an amphibian between being and non-being.