Man is a mystery. It needs to be unravelled, and if you spend your whole life unravelling it, don't say that you've wasted time. I am studying that mystery because I want to be a human being.
Experience has shown, and a true philosophy will always show, that a vast, perhaps the larger portion of the truth arises from the seemingly irrelevant.
I read these words which are the sum of all moral philosophy, and which cut short all the disputes of the casuists: When in doubt if an action is good or bad, refrain.
I am only about half alive - a large part of my strength is consumed in sitting up or walking. My nervous system is a shattered wreck, and I am absolutely bored & listless save when I come upon something which peculiarly interests me. However - so many things do interest me, & interest me intensely, in science, history, philosophy, & literature; that I have never actually desired to die, or entertained any suicidal designs, as might be expected of one with so little kinship to the ordinary features of life.
I do not wish you much happiness--it would bore you; I do not wish you trouble either; but, following the people's philosophy, I will simply repeat: 'Live more' and try somehow not to be too bored; this useless wish I am adding on my own.
I would not think that philosophy and reason themselves will be man's guide in the foreseeable future; however, they will remain the most beautiful sanctuary they have always been for the select few.
The army ages men sooner than the law and philosophy; it exposes them more freely to germs, which undermine and destroy, and it shelters them more completely from thought, which stimulates and preserves.
Only in mathematics and physics was I, through self-study, far beyond the school curriculum, and also with regard to philosophy as it was taught in the school curriculum.
The system of Descartes... seemed to give a plausible reason for all those phenomena; and this reason seemed more just, as it is simple and intelligible to all capacities. But in philosophy, a student ought to doubt of the things he fancies he understands too easily, as much as of those he does not understand.