Buy when most people, including experts, are pessimistic, and sell when they are actively optimistic.
Benjamin GrahamThe correct attitude of the security analyst toward the stock market might well be that of a man toward his wife. He shouldn't pay too much attention to what the lady says, but he can't afford to ignore it entirely. That is pretty much the position that most of us find ourselves vis-à-vis the stock market.
Benjamin GrahamNever mingle your speculative and investment operations in the same account nor in any part of your thinking.
Benjamin GrahamMathematics is ordinarily considered as producing precise and dependable results; but in the stock market the more elaborate and abstruse the mathematics the more uncertain and speculative are the conclusions we draw there from. Whenever calculus is brought in, or higher algebra, you could take it as a warning that the operator was trying to substitute theory for experience, and usually also to give to speculation the deceptive guise of investment.
Benjamin Graham