“If you steal from one author it's plagiarism; if you steal from many it's research.” ~ Wilson Mizner. Quoted in Johnson, A. (1953). The Legendary Mizners. Farrar, Straus & Young, NY, USA
“The kernel, the soul – let us go further and say the substance, the bulk, the actual and valuable material of all human utterances – is plagiarism.” ~ Mark Twain in his letter to Helen Keller, St. Patrick's Day, 1903 -- through Anne Macy. Reprinted in Anne Sullivan Macy, The Story Behind Helen Keller. 1933, Garden City, NY, USA. This was when Helen Keller herself was accused of plagiarism.
These quotes illustrates the problem faced by many students and authors: distinguishing between mere copying of existing thoughts and genuine creativity. This problem is not new.