71. I. Arguments from Analogy: (1) The Enthymeme. -- The enthymeme, says Aristotle, is "a syllogism drawn from certain resemblances or certain marks." -- The "marks" here meant, it must be understood, are not the natural properties of the subject.

Such reasonings are very frequent in ordinary life. E. g.: Most men act from self-interest. Therefore, in this case, Peter acted from self-interest.