Comment by ConceptOfHangxiety on 27/01/2025 at 22:33 UTC

2 upvotes, 1 direct replies (showing 1)

View submission: What makes an argument valid?

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I like this framing for a 1-premise argument because it casts validity according to a conjunction rather than a conditional (the latter being how I was taught).

But how would one prove such an argument through natural deduction?

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Comment by drinka40tonight at 27/01/2025 at 22:40 UTC*

2 upvotes, 2 direct replies

Perhaps it's easier to see if we just use a tautology. So,

1. q

2. Therefore, p v ~p.

The argument is valid, and indeed the conclusion cannot be false. Depending on our natural deduction system, the conclusion will be easily derivable from the particular rules we are using.