The Art of Eloquence
Eloquence is an art of saying things in such a way that those to whom we speak may listen to them without pain and with pleasure; that they feel themselves interested, so that self-love leads them more willingly to reflection upon it. It consists, then, in a correspondence which we seek to establish between the head and the heart of those to whom we speak, on the one hand, and, on the other, between the thoughts and the expressions which we employ. This assumes that we have studied well the heart of man so as to know all its powers and, then, to find the just proportions of the discourse which we wish to adapt to them. We must put ourselves in the place of those who are to hear us, and make trial on our own heart of the turn which we give to our discourse in order to see whether one is made for the other, and whether we can assure ourselves that the hearer will be, as it were, forced to surrender. We ought to restrict ourselves, so far as possible, to the simple and natural, and not to magnify that which is little, or belittle that which is great. It is not enough that a thing be beautiful; it must be suitable to the subject, and there must be in it nothing of excess or defect.
Blaise Pascal, in 'Pensees'