The highest purpose is to have no purpose at all. This puts one in accord with nature, in her manner of operation.
I suppose that the scope and implications of such forces have rendered my personal accounting ritual pretty much obsolete. That's how things sometimes go.
Ideas improve. The meaning of words participates in the improvement. Plagiarism is necessary. Progress implies it. It embraces an author's phrase, makes use of his expressions, erases a false idea, and replaces it with the right idea.