There are problems with all three solutions (free will, determinism, compatibilism) that render each unsatisfying.
Determinism has had criticisms from the very beginning. Democritus and Leucippus (the guys who created the theory of the atoms, and argued that all things that exist are nothing but atoms bumping into each other) recognized that their theory of hard materialistic determinism directly implied that no one could have knowledge of anything besides solipsism. Here is the argument, modernized for your convenience:
Knowledge requires 1)beliefs that are 2)true and 3)justified. (It requires more than this, but all D and L needed to run the argument are these three concepts- beliefs, truth, and justification.) If you don't have a belief, you don't have knowledge. If your belief isn't true, then it isn't knowledge. (In this case we say that someone thought the knew something, but they didn't.) Lastly, if you don't have a reason to believe that your belief is true then you don't have knowledge. That reason is the justification for your belief. Determinism makes it impossible to possess justification.
Here is an example to try to make the definition of knowledge clear before moving to the argument:
Jim sees candy on a table in a store. As a result of his sense perceptions Jim then forms a belief (let's call it B) that candy is on the table in front of him. He leaves the store (or wherever the candy is) and then bumps into Carla. Carla asks Jim what he is thinking about. Jim says 'The candy on the table in the store.' (Naturally. Who wouldn't be?) Carla asks 'How do you know there is candy on the table in the store?' Obviously, Jim's reply is 'Because I saw it.'
Jim's reply is the reason (justification) that makes belief B knowledge. If he had no justification for B he could not hold that belief as knowledge. (Imagine Jim just wanted there to be candy on the table, and didn't check it out. We would blame him if he told people there was candy just because he felt like it.)
Justification is a necessary process each belief must go through in order to be knowledge. But this is vague. 'A necessary process' is about as helpful as 'that mysterious thing in the box I can't open.' If justification is so important we should be clear about what it is. To clarify justification, consider an example that is mildly sci-fi. Suppose a mad scientist procures a child, and then performs a surgery implanting a chip in the child's head to make the child form beliefs. (Dystopian novels sometimes consider examples like this. You can see why. There are nefarious, power-hungry governments that would have wet dreams about control this powerful.) As that child grows, suppose the mad scientist wants to educate the child quickly. So the mad scientist programs the chip to 'teach' the child mathematics very quickly. Imagine the child growing up. Someone, when the child is old enough to understand words, asks 'what is 156 plus 215?' The chip induces the child to believe the answer is 371 before the child has actually reasoned it through for his or her self. So the child answers '371'. They cannot even think otherwise. Suppose every mathematical belief the child possessed was formed this way. Would you say the child is justified in holding these beliefs? I assume you will agree there is a problem here. The child lacks a proper reason for the belief.
And it is here that the question gets complex. I want to say that the child should be able to weigh, reason, measure, think etc. through the problem freely in order to be justified in believing something. It seems to me that free will is required for knowledge. If we are programmed then we lack justification for our beliefs. We cannot have knowledge.
One way people try to avoid this conclusion is be examining what processes cause our beliefs. Evolutionary processes, some say, might help us protect beliefs from this sweeping skeptical argument. But evolution doesn't help either. It is pretty easy to see why. If our beliefs are formed by natural selection then they are subject to the same forces as everything else that evolves are too. Our beliefs, if merely a process of evolution, help us survive and pass on our genes. That's it. Our beliefs might or might not be true. Their actual purpose is reproduction. So my belief that there is a snake and I should avoid it might or might not be true, but it is useful for helping me avoid snakes. Thus if my belief has a ton of false positives (sticks, garden hoses, shadows, thin people, etc) as long as it functions to keep me alive and able to pass on my genes that is what matters. Truth is not selected for.
Thus we get this rather pleasant problem- free will is a mystery. How can we interact with the world, with our bodies, when those things appear to be determined? Determinism implies we cannot have knowledge, including whether or not we are determined. We are cut off from the world.
Which poison do you want?
RE: Determining Determinism