When one's ideas are not challenged, one's ability to defend them weakens.

... All ideas need to be heard, because each idea contains one aspect of the truth. By examining that aspect, we add to our own idea of the truth. Even ideas that have no truth in them whatsoever are useful because by disproving them, we add support to our own ideas.

The validity of all the Inductive Methods depends on the assumption that every event, or the beginning of every phenomenon, must have some cause; some antecedent, upon the existence of which it is invariably and unconditionally consequent.

Trade is a social act.

The English, of all ranks and classes, are at bottom, in all their feelings, aristocrats. They have some concept of liberty, and set some value on it, but the very idea of equality is strange and offensive to them. They do not dislike to have many people above them as long as they have some below them.

The perpetual obstacle to human advancement is custom.

Human beings are no longer born to their place in life...but are free to employ their faculties and such favorable chances as offer, to achieve the lot which may appear to them as desirable.