Hypothetical Syllogism

If you know P implies Q and Q implies R, hypothetical syllogism says you also know P implies R. This is because Q is only acting as an unnecessary middleman in this construction. For example, if you know

“If I am Buffalo, I am in New York.”


“If I am in New York, I am in the United States.”

then you know that if you are in Buffalo, you are in the United States.

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