April 1

There is a countless number of sciences, and every science is limitless and can be pursued forever. This is why the first and main thing to know in every science is which subjects are the most important, which are less important and which are even less important than that. The reason why it is necessary to find this out is that since we cannot study everything, we need to study what is most useful.

1

There is a vast amount of knowledge being accumulated today that is worth studying. Soon our capacities will become too weak and our lives too short to assimilate even a single most useful part of this knowledge. An abundance of wealth is at our service but, having taken it in, we must again discard much of it as useless trash. It would be better to sometimes not burden ourselves with it.

— Kant

2

With our premature and often excessive reading, which gives us so much undigested material, our memory naturally becomes the master of our feelings and tastes; and that is why we often need to exert great mental effort to return the primeval innocence to our feelings, to find our self amid the garbage of other people’s thoughts and opinions, to begin to feel and speak ourselves and, I am almost prepared to say, to at some point begin to exist ourselves.

— Lichtenberg

3

A Persian sage says: “When I was young, I told myself: I want to know all of science. And I had reached a point where there were only a few things left which I did not know, but when I grew old, I saw that my life had passed, and I knew nothing.”

4

Gentlemen, I pray you very solemnly to put that idea of knowing all things in Heaven and Earth out of your hearts and heads. It is very little that we can ever know, either of the ways of Providence, or the laws of existence. But that little is enough, and exactly enough: to strive for more than that little is evil for us; and be assured that beyond the need of our narrow being—beyond the range of the kingdom over which it is ordained for each of us to rule in serene αὐτάρκεια and self-possession, he that increaseth toil, increaseth folly; and he that increaseth knowledge, increaseth sorrow.

— John Ruskin

5

The observations and calculations of astronomers have taught us much that is worthy of wonder; but the most important result of their studies is perhaps the fact that they discovered before us an abyss of everything which we cannot know: without this human knowledge, the mind could never imagine the full extent of this abyss, and contemplating this can produce a great change in how we define the end goals of the activities of reason.

— Kant

6

“There are plants on earth: we can see them, but we could not see them from the moon. On these plants there are leaves, and in these leaves there are tiny animals, but beyond this there is nothing.”—Such presumption! “Complex bodies are composed of elements, and elements are indivisible.”—Such presumption!

— Pascal

7

Do not fear ignorance, fear false knowledge. It is the source of all the evil in the world.

Knowledge is infinite. And that is why the amount by which someone who knows a lot surpasses someone who knows very little is infinitesimally small.