Science is nothing but developed perception, interpreted intent, common sense rounded out and minutely articulated.
So act that your principle of action might safely be made a law for the whole world.
Insanity in individuals is something rare - but in groups, parties, nations and epochs, it is the rule.
Nothing has a stronger influence psychologically on their environment and especially on their children than the unlived life of the parent.
Our problems are man-made, therefore they may be solved by man. And man can be as big as he wants. No problem of human destiny is beyond human beings.
If you think taking care of yourself is selfish, change your mind. If you don't, you're simply ducking your responsibilities.
Refuse to be ill. Never tell people you are ill; never own it to yourself. Illness is one of those things which a man should resist on principle.