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First Mechanization for Validity

Explore how to apply Aristotle’s seven-step algorithm to determine the validity of categorical syllogistic arguments. Understand key steps including ensuring standard forms, identifying major, minor, and middle terms, and using mood and figure to classify and verify logical argument validity.

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Algorithm for computing validity

Judging an argument for being valid is something that resides deep within the realm of our minds. Aristotle’s contributions have made that subconscious process more accessible to us. The following seven stepsAn algorithm is defined as the steps that need to be taken to solve a problem. can analyze any logical argument and, after the last step, output if the input logical argument is valid or invalid. The main idea is to identify the mood and figure of the argument so that it can be easily looked up in the known valid forms; the initial steps all lead up to that.

Step 1: Ensuring categorical syllogism

This first step only ensures that the argument qualifies for all the definitional requirements of a categorical syllogism, i.e., it has two premises and one conclusion. Secondly, it speaks of three categories or terms and distributes them evenly—each term in exactly two of the three propositions.

Step 2: Ensuring standard forms of categorical propositions

Even if the argument is a categorical syllogism, the second step ensures that each of the three propositions is in one of the four standard categorical proposition forms, known as AA, EE ...