For to be possessed of a vigorous mind is not enough;

the prime requisite is rightly to apply it. 

The greatest minds,

as they are capable of the highest excellences, 

are open likewise to the greatest aberrations;

and those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, while they run, forsake it.

-Descartes, Discourse on the Method