"The purpose of the reasoning process, logic's principal concern, is demonstration.  I am not reasoning with you if I simply say that such-and-such is true.  [...]  I must show you that such-and-such is true, and I do that by making an argument.  An argument will only be as good as the statements of which it is composed, and those statements, in turn, will only be as good as the terms of which they are composed.  [...]  Argument is the activity of logic, and any particular argument is a concrete manifestation of the reasoning process."—Thank you, D. Q. McInerny (writer) for Being Logical:  A Guide to Good Thinking, Random House, 2004, p.41