John Stuart Mill
Themes, Arguments, and Ideas
Logic as Induction Before Mill wrote his System of Logic, the system of logic outlined by Aristotle in his Organon (see chapter 2, Aristotle) had been accepted as authoritative. Aristotle's logic is a system of rules for creating syllogisms, arguments that start with a general premise and reach a conclusion about a particular instance, such as “All men are mortal. Socrates is a man. Therefore, Socrates is mortal.” Mill, however, was an empiricist and believed that all knowledge comes to us through our senses and that we only come to believe in any general principles by experiencing many particular instances that bear them out. Although other empiricist philosophers, such as Locke, had argued that experience is the only basis of knowledge, no one before Mill had attempted to write a system of rules, comparable to Aristotle's, for how we arrive at general principles by starting with particulars. Mill established a distinction between deductive logic, in which we extrapolate from general principles, and inductive logic, in which we draw conclusions from specific cases. Mill maintained that inductive logic is the true basis of knowledge.