Here are a few of my favorite words of his, from the late Thoughts on Man (full electronic text can be found here). He's describing the new science of physiognomy as "all a system of fatality" (his sarcastic summary of the phrenologists' position is that "Independently of ourselves, and far beyond our control, we are reserved for good or for evil by the predestinating spirit that reigns over all things"):
Unhappy is the individual who enters himself in this school. He has no consolation, except the gratified wish to know distressing truths, unless we add to this the pride of science, that he has by his own skill and application purchased for himself the discernment which places him in so painful a preeminence. The great triumph of man is in the power of education, to improve his intellect, to sharpen his perceptions, and to regulate and modify his moral qualities. But craniology reduces this to almost nothing, and exhibits us for the most part as the helpless victims of a blind and remorseless destiny.