Ludwig Wittgenstein

Ludwig Josef Johann Wittgenstein (26 April 1889 – 29 April 1951) Austrian philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language. He is considered by some to be the greatest philosopher of the 20th century.

The war has saved my life.
A good objection helps one forward, a shallow objection, even if it is valid, is wearisome. ... The objection does not seize the matter by its root, where the life is, but so far outside that nothing can be rectified even if it is wrong. A good objection helps directly towards a solution, a shallow one must first be overcome and can, from then on, be left to one side. Just as a tree bends at a knot in the trunk in order to grow on.
If suicide is allowed then everything is allowed. If anything is not allowed then suicide is not allowed. This throws a light on the nature of ethics, for suicide is, so to speak, the elementary sin. And when one investigates it, it is like investigating mercury vapor in order to comprehend the nature of vapors.

The limits of your world are the limits of your language

Either my piece is a work of the highest rank, or it is not a work of the highest rank. In the latter (and more probable) case I myself am in favour of it not being printed. And in the former case it's a matter of indifference whether it's printed twenty or a hundred years sooner or later. After all, who asks whether the Critique of Pure Reason, for example, was written in 17x or y.
The older I grow, the more I realize how terribly difficult it is for people to understand each other, and I think that what misleads one is the fact that they all look so much like each other. If some people looked like elephants and others like cats, or fish, one wouldn’t expect them to understand each other and things would look much more like what they really are.
What a picture represents it represents independently of its truth or falsity, by means of its pictorial form.
If someone tells me he has bought the outfit of a tightrope walker I am not impressed until I see what is done with it.

The limits of my language are the limits of my world.

No pain can be greater than the pain of one person. [...] In other words, no suffering can be greater than that of one human being. [...} The whole planet cannot suffer more than a lone soul.
There is not a single philosophical method, though there are indeed methods, different therapies, as it were.
Philosophy is like trying to open a safe with a combination lock: each little adjustment of the dials seems to achieve nothing, only when everything is in place does the door open.
If you want to go down deep you do not need to travel far; indeed, you don’t have to leave your most immediate and familiar surroundings.
Genius is what makes us forget the master's talent.
It was an awful thought to go and sit there among logical positivists ...
The world is my world: this is shown by the fact that the limits of language stand for the limits of my world…I am my world.
And for thoughts there is a time to plough and a time to reap.
The solution of the riddle of life in space and time lies outside space and time. (It is certainly not the solution of any problems of natural science that is required).
The solution of the riddle of life in space and time lies outside space and time.
If a person tells me he has been to the worst places I have no reason to judge him; but if he tells me it was his superior wisdom that enabled him to go there, then I know he is a fraud.
I don't believe I have ever invented a line of thinking, I have always taken one over from someone else. I have simply straightaway seized on it with enthusiasm for my work of clarification. That is how Boltzmann, Hertz, Schopenhauer, Frege, Russell, Kraus, Loos, Weininger, Spengler, Sraffa have influenced me.
What we can't say we can't say, and we can't whistle it either.
What we find in philosophy is trivial; it does not teach us new facts, only science does that. But the proper synopsis of these trivialities is enormously difficult, and has immense importance. Philosophy is in fact the synopsis of trivialities.
The more closely we examine actual language, the greater becomes the conflict between it and our requirement. The conflict becomes intolerable; the requirement is now in danger of becoming vacuous. — We have got on to slippery ice where there is no friction, and so, in a certain sense, the conditions are ideal; but also, just because of that, we are unable to walk. We want to walk: so we need friction. Back to the rough ground!
The war saved my life. I don't know what I would have done without it. Now I should have the chance to be a decent human being, for I'm standing eye to eye with death.
Man has to awaken to wonder — and so perhaps do peoples. Science is a way of sending him off to sleep again.
My aim is: to teach you to pass from a piece of disguised nonsense to something that is patent nonsense.
I know that human beings on the average are not worth much anywhere, but here they are much more good-for-nothing and irresponsible than elsewhere.
Perhaps you regard this thinking about myself as a waste of time - but how can I be a logician before I'm a human being! Far the most important thing is to settle accounts with myself!
Don't get involved in partial problems, but always take flight to where there is a free view over the whole single great problem, even if this view is still not a clear one.