One man may have some special knowledge at first-hand about the character of a river or a spring, who otherwise knows only what everyone else knows. Yet to give currency to this shred of information, he will undertake to write on the whole science of physics. From this fault many great troubles spring.
Michel de MontaigneWe are nearer neighbors to ourselves than the whiteness of snow or the weight of stones are to us: if man does not know himself, how should he know his functions and powers?
Michel de Montaigne