Truths are known to us in two ways: some are known directly, and of themselves; some through the medium of other truths. The former are the subject of Intuition, or Consciousness; the latter, of Inference; the latter of Inference. The truths known by Intuition are the original premisses, from which all others are inferred.

The guesses which serve to give mental unity and wholeness to a chaos of scattered particulars, are accidents which rarely occur to any minds but those abounding in knowledge and disciplined in intellectual combinations.

It's hardly possible to overstate the value, in the present state of human improvement, of placing human beings in contact with other persons dissimilar to themselves, and with modes of thought and action unlike those with which they are familiar. Such communication has always been... one of the primary sources of progress.

Since the general or prevailing opinion on any subject is rarely or never the whole truth, it is only by the collision of adverse opinion that the remainder of the truth has any chance of being supplied.

The will of the people, moreover, practically means the will of the most numerous or the most active part of the people; the majority, or those who succeed in making themselves accepted as the majority; type people, consequently, may desire to oppress a part of their number; and precautions are as much needed against this as against any other abuse of power.

A man of clear ideas errs grievously if he imagines that whatever is seen confusedly does not exist; it belongs to him, when he meets with such a thing, to dispel the midst, and fix the outlines of the vague form which is looming through it.

It is given to no human being to stereotype a set of truths, and walk safely by their guidance with his mind's eye closed.