Let one persuade many, and he becomes confirmed and convinced, and cares for no better evidence.
The questions of philosophy proper are human desires and fears and aspirations - human emotions - taking an intellectual form.
The accidental causes of science are only accidents relatively to the intelligence of a man.
By what criterion... can we distinguish among the numberless effects, that are also causes, and among the causes that may, for aught we can know, be also effects, - how can we distinguish which are the means and which are the ends?
All observers not laboring under hallucinations of the senses are agreed, or can be made to agree, about facts of sensible experience, through evidence toward which the intellect is merely passive, and over which the individual will and character have no control.