Hmm ... if we know Kit Yates is reliably a truth teller, both statements about James could equally be true? If we know that Kit occasionally misses typos, then we might be uncertain. Knowing you though, its ok.
You've told us James IS a mathematician. How he earns a living doesn't alter that. His day job could be refuse collector or chef or carer. He's still a mathematician. </pedant>
Yes, this is a fair point. I was using the word 'mathematician' in a strict sense to mean someone who earns a living doing maths, but you are right the true definition of mathematician is much broader than that. Still though it is an extra restriction that means set 2 is a subset of set 1.
Hmm ... if we know Kit Yates is reliably a truth teller, both statements about James could equally be true? If we know that Kit occasionally misses typos, then we might be uncertain. Knowing you though, its ok.
Well, yes. But also no.
You've told us James IS a mathematician. How he earns a living doesn't alter that. His day job could be refuse collector or chef or carer. He's still a mathematician. </pedant>
Yes, this is a fair point. I was using the word 'mathematician' in a strict sense to mean someone who earns a living doing maths, but you are right the true definition of mathematician is much broader than that. Still though it is an extra restriction that means set 2 is a subset of set 1.