We have been trying to point out that this concept of an indefinitely favorable future is dangerous, even if it is true; because even if it is true you can easily overvalue the security, since you make it worth anything you want it to be worth. Beyond this, it is particularly dangerous too, because sometimes your ideas of the future turn out to be wrong. Then you have paid an awful lot for a future that isn't there. Your position then is pretty bad.
Benjamin GrahamAlways remember that market quotations are there for convenience, either to be taken advantage of or to be ignored.
Benjamin GrahamBuy when most people, including experts, are pessimistic, and sell when they are actively optimistic.
Benjamin GrahamThe beauty of periodic rebalancing is that it forces you to base your investing decisions on a simple, objective standard.
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