Why should they be? — Tristan L

The truth value of statements about the furure is controversial or so I heard.

Yes, and that’s precisely why we look at them. If we only consider either true or false propositions, then we presuppose PB from the start, so we won’t find anything violating PB while still obeying LEM because PB is stronger than LEM. However, to see the difference between two principles, it’s best to take a look at something which obeys one but violates the other, and that’s exactly what propositions about the future do: they obey LEM but violate PB. This makes clear that LEM says that for every proposition A, we have TRUE(A v ~A), while PB makes the stronger claim that for every proposition A, we have TRUE(A) v TRUE(~A).

You may also want to check out what I said earlier and tell me what you think.

Yes, and that’s precisely why we look at them — Tristan L

I thought that's precisely why we should avoid them - why add fuel to fire and make the matter more complicated?. Let's consider the LEM and the PB with respect to statements about the present first shall we. Please comment on whether I've understood PB and LEM as it concerns either propositions that are timeless or propositions about the present. Thank you for your concern.

Regarding timeless propositions or propositions about the present or past, I still think that you have misunderstood LEM. In general, (TRUE(A) v TRUE(B)) is stronger than TRUE(A v B). Hence, (TRUE(A) v TRUE(~A) for every proposition A) is a stronger principle than (TRUE(A v ~A) for every proposition A). The latter is LEM, but the former is the principle which you incorrectly (according to my understanding) regard as equivalent to LEM when it is indeed nothing other than PB. The two are equivalent only if we already presuppose the bivalence principle PB that each proposition A is either true (we have TRUE(A)) or false (we have TRUE(~A)). Bear in mind that falsehood is just truth of negation, that is, for every proposition A, FALSE(A) = TRUE(~A) by definition.