Metaphysics is a dark ocean without shores or lighthouse, strewn with many a philosophic wreck.

Only two things are infinite, the universe and human stupidity, and I’m not sure about the former.

Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe.

The farther backward you can look, the farther forward you can see.

All human evil comes from a single cause, man’s inability to sit still in a room.

Life without liberty is like a body without spirit.

A man should be upright, not be kept upright.

The reason we want to go on and on is because we live in an impoverished present.

When a man bleeds inwardly, it is a dangerous thing for himself; but when he laughs inwardly, it bodes no good to other people.

Life is a series of commas, not periods.

Anything for the quick life, as the man said when he took the situation at the lighthouse.

Everything that happens happens as it should, and if you observe carefully, you will find this to be so.

No obligation to do the impossible is binding.

Observe constantly that all things take place by change, and accustom thyself to consider that the nature of the Universe loves nothing so much as to change the things which are, and to make new things like them.

Everything can change at any moment, suddenly and forever.

Knowledge is true opinion.

In order to exist, man must rebel, but rebellion must respect the limits that it discovers in itself – limits where minds meet, and in meeting, begin to exist.

There is no doubt that life is given us, not to be enjoyed, but to be overcome; to be got over.

It is beyond a doubt that all our knowledge begins with experience.

Life and death are one thread, the same line viewed from different sides.

I have always held firmly to the thought that each one of us can do a little to bring some portion of misery to an end.

The love of economy is the root of all virtue.

It is best to rise from life as from a banquet, neither thirsty nor drunken.

Mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed.

Poetry is finer and more philosophical than history; for poetry expresses the universal, and history only the particular.

So act that your principle of action might safely be made a law for the whole world.

All men are equal before fish.

I have just got a new theory of eternity.

I believe everyone should have a broad picture of how the universe operates and our place in it. It is a basic human desire. And it also puts our worries in perspective.

If you can look into the seeds of time, and say which grain will grow and which will not, speak then unto me.

Light troubles speak; the weighty are struck dumb.

It is incomprehensible that God should exist, and it is incomprehensible that he should not exist.

Before the effect one believes in different causes than one does after the effect.

The abdomen is the reason why man does not readily take himself to be a god.

There is a blessed necessity by which the interest of men is always driving them to the right; and, again, making all crime mean and ugly.

We are sinful not only because we have eaten of the Tree of Knowledge, but also because we have not yet eaten of the Tree of Life. The state in which we are is sinful, irrespective of guilt.

One’s philosophy is not best expressed in words; it is expressed in the choices one makes… and the choices we make are ultimately our responsibility.

You shall know the truth, and the truth shall make you mad.

I did used to have nightmares about the idea that when I die, there is a spark of consciousness which basically creates the world. ‚Is the world going to disappear if this spark of consciousness disappears? And how do I know it won’t? How do I know there’s anything there except what I’m conscious of?‘

I am a little too absorbed by science to be able to philosophise much; but the more I look into myself, the more I find myself possessed by the conviction that it is only the science of Christ running through all things, that is to say true mystical science, that really matters. I let myself get caught up in the game when I geologise.

Every tyrant who has lived has believed in freedom for himself.

I am a part of everything that I have read.

A man who suffers before it is necessary, suffers more than is necessary.

Having nothing, nothing can he lose.

Every man casts a shadow; not his body only, but his imperfectly mingled spirit. This is his grief. Let him turn which way he will, it falls opposite to the sun; short at noon, long at eve. Did you never see it?

Friendship is unnecessary, like philosophy, like art… It has no survival value; rather it is one of those things that give value to survival.

I look upon death to be as necessary to our constitution as sleep. We shall rise refreshed in the morning.

The future influences the present just as much as the past.

But at any rate, the point is that God is what nobody admits to being, and everybody really is.

I read Plato’s ‚Republic.‘ I read it through about five times until I could actually understand it.

Freedom is not worth having if it does not connote freedom to err.

To attain any assured knowledge about the soul is one of the most difficult things in the world.

There is not a more unhappy being than a superannuated idol.

Where there is reverence there is fear, but there is not reverence everywhere that there is fear, because fear presumably has a wider extension than reverence.

The utmost extent of man’s knowledge, is to know that he knows nothing.

The greatest and most important problems of life are all fundamentally insoluble. They can never be solved but only outgrown.

It is a bit embarrassing to have been concerned with the human problem all one’s life and find at the end that one has no more to offer by way of advice than ‚try to be a little kinder.‘

My theory has always been, that if we are to dream, the flatteries of hope are as cheap, and pleasanter, than the gloom of despair.

The light which puts out our eyes is darkness to us. Only that day dawns to which we are awake. There is more day to dawn. The sun is but a morning star.

If God did not exist, it would be necessary to invent Him.

Whatever universe a professor believes in must at any rate be a universe that lends itself to lengthy discourse. A universe definable in two sentences is something for which the professorial intellect has no use. No faith in anything of that cheap kind!