3 Chapter 7: Categorical Syllogisms
Patrick J. Hurley
Reading 1: Logic Categorical Syl Hurley 5.1–The mood and figure method
Reading 2: Logic Categorical Syllogisms Hurley 5.2 –The Venn diagram method
PowerPoint: Categorical Syllogisms
Audio/Video Lesson: Categorical Syllogisms Hurley 5.1-5.2
If all humans are mortal, and Socrates is a human, does it follow that Socrates is mortal? If all humans are mortal, and some robots are mortal, does it follow that some robots are human?
In this chapter we learn more about Aristotle’s categorical logic as it applies to arguments such as these. In readings written once again by Patrick Hurley, we learn about categorical syllogisms, or two-premise arguments comprised of categorical propositions. After learning about the qualities of categorical syllogisms known as mood and figure, which can help to identify when a categorical syllogism is valid, we will learn a second method for testing for validity–the three ring Venn diagram method. This chapter builds on the skills developed in Chapter Six.