Mathematics 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 GrahamThose with the enterprise lack the money and those with the money lack the enterprise to buy stocks when they are cheap.
Benjamin GrahamThe distinction between investment and speculation in common stocks has always been a useful one and its disappearance is cause for concern.
Benjamin GrahamSpeculative stock movements are carried too far in both directions, frequently in the general market and at all times in at least some of the individual issues.
Benjamin Graham