I never refuted your hypothesis, I just pointed out the fact that the universe being deterministic has nothing to do with whether it's worth it for you to believe that you can achieve things and therefore try. Nor did I say that whether you believe it depends on something you can control. Assuming determinism, it's always worth it to believe that you can achieve things and try, even if it's as a result of me saying this.
Believing -> trying -> accomplishing
The arrows are causal links. Whether the state of believing is achieved through chance or choice is irrelevant.
No, that's not what I'm saying. And I never said that you're a being with no free will. In fact, you have free will. It's just that your idea of free will refers to a deterministic process if we're in a deterministic universe.
It's not possible to know what a non-deterministic process is in a deterministic universe. If you have faith that the universe is deterministic, then your definition of "non-deterministic" is equivalent to "deterministic" because you've never observed anything other than deterministic processes.
The only reason we're even able to talk about this in a meaningful way is because we both know your assumption is just an assumption rather than the truth, and we abstractly distinguished some phenomena as different from others, and say that one group defines determinism, while the other group defines non-determinism.
But since you're assuming that the universe is deterministic, then according to you, free will means the capacity for deterministic decision-making, which you have. The process of decision-making still happens in your brain, it's just a deterministic process.
I've merely pointed out that accomplishing something is a state of reality that can only come after trying to do that thing. If you don't try, you won't accomplish. And if you don't believe you should try, you won't try. So if you don't believe you should try, you won't accomplish. All of these statements are true in a deterministic universe.
If you don't believe you should try, then there can only be one outcome: you won't accomplish. If you believe you should try, then there can also only be one outcome (according to your assumption), but you don't know what it will be. The universe may have predestined you to accomplish something, but it can only begin with you believing you can do it. Why not start believing you can do it? Believing is a necessary precondition to accomplishment, even if that belief is predetermined. Just do it.
Believing -> trying -> accomplishing
The arrows are causal links. Whether the state of believing is achieved through chance or choice is irrelevant.