Logical thinking is the second educational legacy of idealism. Dialogical approaches such as those used by Plato led to logical thinking and the rules that were laid down by Plato’s successor, Aristotle. Some of Aristotle’s most important rules concern concept formation and deductive reasoning. Deductive reasoning progresses from the general case to the particular case by logical inference. Aristotle (1995) offers a well-known example in a three-step argument called a syllogism: