As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.
The length of a man's outspread arms is equal to his height.
Art is never finished, only abandoned.
But to me all sciences seem vain and full of error that are not born of experience, mother of all certainty, and do not terminate in an actual experience.
He who thinks little errs much.
The motive power is the cause of all life.