There is no greater impediment to the advancement of knowledge than the ambiguity of words. To this chiefly it is owing that we find sects and parties in most branches of science [and politics]; and disputes that are carried on from age to age, without being brought to issue.

Every theory in philosophy, which is built on pure conjecture, is an elephant; and every theory that is supported partly by fact, and partly by conjecture, is like Nebuchadnezzar's image, whose feet were partly of iron, and partly of clay.

For the perception of the beautiful we have the term "taste"--a metaphor taken from that which is passive in the body and transferred to that which is active in the mind.

And, if we have any evidence that the wisdom which formed the plan is in the man, we have the very same evidence, that the power which executed it is in him also.

It appears evident, therefore, that those actions only can truly be called virtuous, and deserving of moral approbation, which the agent believed to be right, and to which he was influenced, more or less, by that belief.

There is no greater impediment to the advancement of knowledge than the ambiguity of words. To this chiefly it is owing that we find sects and parties in most branches of science [and politics]; and disputes that are carried on from age to age, without being brought to issue.

Every conjecture we can form with regard to the works of God has as little probability as the conjectures of a child with regard to the works of an adult.