"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. In forty-four years of Wall Street experience and study I have never seen dependable calculations made about common stock values or related investment policies that went beyond dimple arithmetic or the most elementary algebra. 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