In his answer to Q2 and Q3, the fatalist is too quickly jumping from premises about what actually happens (and what else can consistently happen in the same situations) to conclusions about how things would or could have gone differently.Compare:
You can have (2) without (1). For example, let A be "There is a reporter hidden behind the curtain taping your conversation" and let B be "What you say appears in tomorrow's paper." It's not surprising that if A then B. So (1) is false. However, if there really is a hidden reporter, then you may not notice him, and you may well be surprised to see your words in the paper the next day. That is, it could be that A and that as a result you're surprised by the fact that B.
You can also have (1) without (2). For example, let A be "An assassin is secretly tracking your movements." and let B is "You make it to class today in good health." If A is true, you may not know that it's true, and so you may be completely unsurprised to arrive at class in good health. That is, (2) is false. However, you may find the claim "You arrived in good health even though an assassin is tracking you" to be surprising. So, (1) may be true. (Perhaps the surprising explanation behind (1) is that your assassin values philosophy too much to kill you on the way to class...)
So (1) and (2) can clearly come apart.
In the same way, these two claims are also different:
(4) says that anyone who's in fact single is essentially spouseless: there is no possible situation in which they have a spouse. That's a very extreme and implausible claim.
(3) on the other hand, merely said that you can't be single and have a spouse at the same time. That claim is obviously correct.In his treatment of Q2 and Q3, I think the fatalist is confusing claims of this sort. He's confusing the TRUE claim:
As we proceed, we'll encounter other arguments for claims like 6 and 6*. So I don't yet want to say that 6 and 6* are definitively false. Some of the other arguments we look at may persuade some of you to accept them. What I do want to persuade you of now is that so far we've seen no reason to accept 6 and 6*. The kind of reasoning the fatalist appeals to, based merely on the premise that there are already truths about how the future will turn out, doesn't support 6 and 6*.