The despotism of custom is everywhere the standing hindrance to human advancement.

Most persons have but a very moderate capacity of happiness. Expecting...in marriage a far greater degree of happiness than they commonly find, and knowing not that the fault is in their own scanty capability of happiness.

This is what writers mean when they say that the notion of cause involves the idea of necessity. If there be any meaning which confessedly belongs to the term necessity, it is unconditionalness. That which is necessary, that which must be, means that which will be, whatever supposition we may make in regard to all other things.

The ends of scientific classification are best answered, when the objects are formed into groups respecting which a greater number of general propositions can be made, and those propositions more important, than could be made respecting any other groups into which the same things could be distributed. ... A classification thus formed is properly scientific or philosophical, and is commonly called a Natural, in contradistinction to a Technical or Artificial, classification or arrangement.

All women are brought up from the very earliest years in the belief that their ideal of character is the very opposite to that of men; not self-will, and government by self-control, but submission and yielding to the control of others. All the moralities tell them that it is their nature to live for others; to make complete abnegation of themselves, and to have no life but in their affections.

The idea is essentially repulsive, of a society held together only by the relations and feelings arising out of pecuniary interest.

The beliefs which we have most warrant for have no safeguard to rest on but a standing invitation to the whole world to prove them unfounded. If the challenge is not accepted, or is accepted and the attempt fails, we are far enough from certainty still; but we have done the best that the existing state of human reason admits of; we have neglected nothing that could give the truth a chance of reaching us.