Stolen thoughts on stealing thoughts:

On the direction of E2:

Well, history and tradition testify that the heart is just about what it was in the beginning; it has undergone no shade of change. Its good and evil impulses and their consequences are the same to-day that they were in Old Bible times, in Egyptian times, in Greek times, in Middle Age times, in Twentieth Century times. There has been no change.

Letter, March 14, 1905, Mark Twain's Letters

On the work of others, purloined or no:

Oh, dear me, how unspeakably funny and owlishly idiotic and grotesque was that "plagiarism" farce! As if there was much of anything in any human utterance, oral or written, except plagiarism! The kernal, the soul -- let us go further and say the substance, the bulk, the actual and valuable material of all human utterances -- is plagiarism. For substantially all ideas are second-hand, consciously and unconsciously drawn from a million outside sources, and daily used by the garnerer with a pride and satisfaction born of the superstition that he originated them; whereas there is not a rag of originality about them anywhere except the little discoloration they get from his mental and moral calibre and his temperament, and which is revealed in characteristics of phrasing. When a great orator makes a great speech you are listening to ten centuries and ten thousand men -- but we call it his speech, and really some exceedingly small portion of it is his. But not enough to signify. It is merely a Waterloo. It is Wellington's battle, in some degree, and we call it his; but there are others that contributed. It takes a thousand men to invent a telegraph, or a steam engine, or a phonograph, or a photograph, or a telephone or any other important thing -- and the last man gets the credit and we forget the others. He added his little mite -- that is all he did. These object lessons should teach us that ninety-nine parts of all things that proceed from the intellect are plagiarisms, pure and simple; and the lesson ought to make us modest. But nothing can do that.

Samuel Clemens in a letter to Helen Keller, 1903

On adding the work of others, with purpose:

PLAGIARISM, n. A literary coincidence compounded of a discreditable priority and an honorable subsequence.

PLAGIARIZE, v. To take the thought or style of another writer whom one has never, never read.

On those who fear change:

CYNIC, n. A blackguard whose faulty vision sees things as they are, not as they ought to be. Hence the custom among the Scythians of plucking out a cynic's eyes to improve his vision.

Ambrose Bierce - the Devil's Dictionary