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## Wireless Philosophy

### Course: Wireless Philosophy>Unit 2

Lesson 3: Language

# Language: Conditionals, Part 3

In part 3 of the series on conditionals, Justin picks up where part 2 leaves off, introducing an alternative theory of conditionals: the strict conditional theory. According to the strict theory, conditionals express necessary connections between their antecedent and consequent. Justin shows how this theory avoids the problems facing the material conditional theory. However, the strict theory turns out to face a similar problem of its own!

Speaker: Dr. Justin Khoo, Assitant Professor, M.I.T.

## Want to join the conversation?

• There is a way that 2+2=4 is false. If we are working modulo 3, then we find that 2+2=1, and not 4, because 4 exists only as 1. I think this is exposing a hole in "must be true", that lots of things come extremely close to being necessarily true and truths that don't have means of being made false under special circumstances.
Is this anomaly isolated? Are we allowed to take something with an arbitrarily small probability of being false as being true?
(1 vote) • The definition of 4 is 1+1+1+1. The definition of 2 is 1+1. So 2+2 is literally 1+1+1+1 which is by definition 4. If we were to try and add that we are working in mod 3, then 2+2 would still be 4, but 4 mod 3 would equal 1. But that is not the real problem.

The problem is that when he says that 2+2=4, we are not in mod 3. Mathematical notation requires that the modulus be stated. So it would be true that 2+2=4, but if we wanted to work in modulo 3, then we need to state that, because otherwise we are not. 