What Determinists Want
Compatibilism is the most common form of determinism today.
Compatibilism argues that determinism and free will are compatible. It says man is free as long as his own will is one of the steps in the causal chain, even if his choices are completely predetermined for physical reasons or preordained by God.
The core idea of compatibilism is that man can only be morally responsible for his actions if his will is determined.
If our actions are caused by chance, there can be no responsibility.

Giving Determinists What They Say They Want 1
1. They Want Determinism. So we ask them two simple questions:

"First, Do you agree that there is some physical indeterminism in the universe?" By which of course we mean quantum mechanical uncertainty.

"And second, do you agree that quantum mechanical indeterminism normally has no observable effect on large physical structures?" By which we mean that the world is "adequately determined."

2. They Want Intelligible Freedom. We ask a third simple question,

"If the indeterminism only provided genuine possible alternatives for action and thought, if it did not impair the adequately determined will in any way, if it does not directly cause any action, is such a freedom and element of unpredictability acceptable?"

3. They Want Moral Responsibility. Finally, we ask one last question,

"Would you agree that the adequately determined will, making its selection from among such unpredictable actions or thoughts, can be held morally responsible for its choices?"

An example of an event that is not strictly caused is one that depends on chance, like the flip of a coin. If the outcome is only probable, not certain, then the event can be said to have been caused by the coin flip, but the head or tails result itself was not predictable. So this causality, which recognizes prior events as causes, is undetermined and the result of chance alone.
We call this "soft" causality. Events are caused by prior (uncaused) events, but not determined by events earlier in the causal chain, which has been broken by the uncaused cause.
The role of determinism is critical for the question of free will. Strict determinism implies just one possible future. Chance means that the future is unpredictable. Chance allows alternative futures and the question becomes how the one actual present is realized from these potential alternatives.
The departure required from strict determinism is very slight. It does not impair the adequately determined will.
Even in a world that contains quantum uncertainty, macroscopic objects are determined to an extraordinary degree. Newton's laws of motion are deterministic enough to send men to the moon and back. Our Cogito model of the Macro Mind is large enough to ignore quantum uncertainty for the purpose of the reasoning will. The neural system is robust enough to insure that mental decisions are reliably transmitted to our limbs.
we see a world of
soft causality and adequate determinism
We call this determinism, only ineffective for extremely small structures, "adequate determinism." Determinism is adequate enough for us to predict eclipses for the next thousand years or more with extraordinary precision.
And while there is no deterministic causal chain, events still have causes, albeit some that were themselves not completely predictable. The "causa sui" self-caused causes initiate new "soft" causal chains.
Dogmas of Determinsm

Belief in strict determinism, in the face of physical evidence for indeterminism, is only tenable today for dogmatic philosophy. We survey ten modern dogmas of determinism.
The presence of quantum uncertainty leads some philosophers to call the world indetermined. If any event is undetermined, then "indeterminism is true." Logically this is the case, but it is somewhat misleading, with strong negative connotations, when most events are overwhelmingly "adequately determined."
There is no problem imagining that the three traditional mental faculties of reason - perception, conception, and comprehension - are all carried on with adequate determinism in a physical brain where quantum events do not interfere with normal operations.
There is also no problem imagining a role for randomness in the brain in the form of quantum level noise. Noise can introduce random errors into stored memories. Noise could create random associations of ideas during memory recall. This randomness may be driven by microscopic fluctuations that are amplified to the macroscopic level.
Our Macro Mind needs the Micro Mind for the free action items and thoughts in an Agenda of alternative possibilities to be de-liberated by the will. The random Micro Mind is the "free" in free will and the source of human creativity. The adequately determined Macro Mind is the "will" in free will that de-liberates, choosing actions for which we can be morally responsible.
For Teachers
Excerpts from On Giving Libertarians What They Say They Want, by Daniel Dennett (1978) Chapter 15 of Brainstorms, Bradford Books (p.286)

Why is the free will problem so persistent? Partly, I suspect, because it is called the free will problem.

But we don't have any good theories. Since the case for determinism is persuasive and since we all want to believe we have free will, compatibilism is the strategic favorite, but we must admit that no compatibilism free of problems while full of the traditional flavors of responsibility, has yet been devised.

The alternatives to compatibilism are anything but popular. Both the libertarian and the hard determinist believe that free will and determinism are incompatible. The hard determinist says: "So much of the worse for free will." The libertarian says: "So much the worse for determinism," at least with regard to human action. Both alternatives have been roundly and routinely dismissed as at best obscure, at worst incoherent. But alas for the compatibilist, neither view will oblige us by fading away. Their persistence...probably has many explanations. I hope to diagnose just one of them.

every event is either causally determined or random
In a recent paper, David Wiggins has urged us to look with more sympathy at the program of libertarianism.' Wiggins first points out that a familiar argument often presumed to demolish libertarianism begs the question. The first premise of this argument is that every event is either causally determined or random. Then since the libertarian insists that human actions cannot be both free and determined, the libertarian must be supposing that any and all free actions are random. But one would hardly hold oneself responsible for an action that merely happened at random, so libertarianism, far from securing a necessary condition for responsible action, has unwittingly secured a condition that would defeat responsibility altogether. This standard objection to libertarianism, then, assumes what it must prove; it fails to show that undetermined action would be random action, and hence action for which we could not be held responsible.

But is there in fact any reasonable hope that the libertarian can find some defensible ground between the absurdity of "blind chance" on the one hand and on the other what Wiggins calls the cosmic unfairness of the determinist's view of these matters? Wiggins thinks there is.

Maxwell's Demon could not defeat the Second Law. And "intelligence" here suggests something non-physical.
He draws our attention to a speculation of Russell's: "It might be that without infringing the laws of physics, intelligence could make improbable things happen, as Maxwell's demon would have defeated the second law of thermo-dynamics by opening the trap door to fast-moving particles and closing it to slow-moving particles."' Wiggins sees many problems with the speculation, but he does, nevertheless, draw a glimmer of an idea from it.

Let us return then, to Russell's speculation that intelligence might make improbable things happen. Is there any way that something like this could be accomplished? The idea of intelligence exploiting randomness is not unfamiliar. The poet, Paul Valéry, nicely captures the basic idea:

This is Poincaré's idea, as discussed by Hadamard, at a 1937 conference attended by Valéry and many others.
It takes two to invent anything. The one makes up combinations; The other one chooses, recognizes what he wishes and what is important to him in the mass of the things which the former has imparted to him. What we call genius is much less the work of the first one than the readiness of the second one to grasp the value of what has been laid before him and to choose it.*
Here we have the suggestion of an intelligent selection from what may be a partially arbitrary or chaotic or random production, and what we need is the outline of a model for such a process in human decision-making.

This is our Cogito model - free and uncaused alternate possibilities followed by an adequately determined will making a responsible choice.
The model of decision making I am proposing has the following feature: when we are faced with an important decision, a consideration-generator whose output is to some degree undetermined produces a series of considerations, some of which may of course be immediately rejected as irrelevant by the agent (consciously or unconsciously). Those considerations that are selected by the agent as having a more than negligible bearing on the decision then figure in a reasoning process, and if the agent is in the main reasonable, those considerations ultimately serve as predictors and explicators of the agent's final decision. What can be said in favor of such a model, bearing in mind that there are many possible substantive variations on the basic theme?

intelligence makes a difference
First, I think it captures what Russell was looking for. The intelligent selection, rejection and weighting of the considerations that do occur to the subject is a matter of intelligence making the difference. Intelligence makes the difference here because an intelligent selection and assessment procedure determines which microscopic indeterminacies get amplified as it were, into important macroscopic determiners of ultimate behavior.

Second, I think it installs indeterminism in the right place for the libertarian, if there is a right place at all. The libertarian could not have wanted to place the indeterminism at the end of the agent's assessment and deliberation. It would be insane to hope that after all rational deliberation had terminated with an assessment of the best available course of action, indeterminism would then intervene to flip the coin before action. It is a familiar theme in discussions of free will that the important claim that one could have done otherwise under the circumstances is not plausibly construed as the claim that one could have done otherwise given exactly the set of convictions and desires that prevailed at the end of rational deliberation. So if there is to be a crucial undetermined nexus, it had better be prior to the final assessment of the considerations on the stage, which is right where we have located it.

Third, I think that the model is recommended by considerations that have little or nothing to do with the free will problem. It may well turn out to be that from the point of view of biological engineer, it is just more efficient and in the end more rational that decision making should occur in this way. Time rushes on, and people must act, and there may not be time for a person to canvass all his beliefs, conduct all the investigations and experiments that he would see were relevant, assess every preference in his stock before acting, and it may be that the best way to prevent the inertia of Hamlet from overtaking us is for our decision-making processes to be expedited by a process of partially random generation and test. Even in the rare circumstances where we know there is, say, a decision procedure for determining the optimal solution to a decision problem, it is often more reasonable to proceed swiftly and by heuristic methods, and this strategic principle may in fact be incorporated as a design principle at a fairly fundamental level of cognitive-conative organization.

education makes a difference
A fourth observation in favor of the model is that it permits moral education to make a difference, without making all of the difference. A familiar argument against the libertarian is that if our moral decisions were not in fact determined by our moral upbringing, or our moral education, there would be no point in providing such an education for the young. The libertarian who adopted our model could answer that a moral education, while not completely determining the generation of considerations and moral decision-making, can nevertheless have a prior selective effect on the sorts of considerations that will occur. A moral education, like mutual discussion and persuasion generally, could adjust the boundaries and probabilities of the generator without rendering it deterministic.

we are the authors of our moral decisions
Fifth — and I think this is perhaps the most important thing to be said in favor of this model — it provides some account of our important intuition that we are the authors of our moral decisions. The unreflective compatibilist is apt to view decision-making on the model of a simple balance or scale on which the pros and cons of action are piled. What gets put on the scale is determined by one's nature and one's nurture, and once all the weights are placed, gravity as it were determines which way the scale will tip, and hence determines which way we will act. On such a view, the agent does not seem in any sense to be the author of the decisions, but at best merely the locus at which the environmental and genetic factors bearing on him interact to produce a decision. It all looks terribly mechanical and inevitable, and seems to leave no room for creativity or genius. The model proposed, however, holds out the promise of a distinction between authorship and mere implication in a causal chain.*

Finally, the model I propose points to the multiplicity of decisions that encircle our moral decisions and suggests that in many cases our ultimate decision as to which way to act is less important phenomenologically as a contributor to our sense of free will than the prior decisions affecting our deliberation process itself: the decision, for instance, not to consider any further, to terminate deliberation; or the decision to ignore certain lines of inquiry.

These prior and subsidiary decisions contribute, I think, to our sense of ourselves as responsible free agents, roughly in the following way: I am faced with an important decision to make, and after a certain amount of deliberation, I say to myself: "That's enough. I've considered this matter enough and now I'm going to act," in the full knowledge that I could have considered further, in the full knowledge that the eventualities may prove that I decided in error, but with the acceptance of responsibility in any case.

I have recounted six recommendations for the suggestion that human decision-making involves a non-deterministic generate-and-test procedure. First, it captures whatever is compelling in Russell's hunch. Second, it installs determinism in the only plausible locus for libertarianism (something we have established by a process of elimination). Third, it makes sense from the point of view of strategies of biological engineering. Fourth, it provides a flexible justification of moral education. Fifth, it accounts at least in part for our sense of authorship of our decisions. Sixth, it acknowledges and explains the importance of decisions internal to the deliberation process. It is embarrassing to note, however, that the very feature of the model that inspired its promulgation is apparently either gratuitous or misdescribed or both, and that is the causal indeterminacy of the generator. We have been supposing, for the sake of the libertarian, that the process that generates considerations for our assessment generates them at least in part by a physically or causally undetermined or random process. But here we seem to be trading on yet another imprecision or ambiguity in the word "random". When a system designer or programmer relies on a "random" generation process, it is not a physically undetermined process that is required, but simply a patternless process. Computers are typically equipped with a random number generator, but the process that generates the sequence is a perfectly deterministic and determinate process. If it is a good random number generator (and designing one is extraordinarily difficult, it turns out) the sequence will be locally and globally patternless. There will be a complete absence of regularities on which to base predictions about unexamined portions of the sequence.

After an excellent discussion of the benefits of randomness, Dennett blunders by assuming that randomness might be simply deterministic pseudo-randomness, not the real chance of quantum uncertainty.
Isn't it the case that the new improved proposed model for human deliberation can do as well with a random-but-deterministic generation process as with a causally undetermined process? Suppose that to the extent that the considerations that occur to me are unpredictable, they are unpredictable simply because they are fortuitously determined by some arbitrary and irrelevant factors, such as the location of the planets or what I had for breakfast. It appears that this alternative supposition diminishes not one whit the plausibility or utility of the model that I have proposed. Have we in fact given the libertarians what they really want without giving them indeterminism? Perhaps. We have given the libertarians the materials out of which to construct an account of personal authorship of moral decisions, and this is something that the compatibilistic views have never handled well. But something else has emerged as well. Just as the presence or absence of macroscopic indeterminism in the implementation style of intentional actions turned out to be something essentially undetectable from the vantage point of our Lebenswelt, a feature with no significant repercussions in the "manifest image", to use Sellars' term, so the rival descriptions of the consideration generator, as random-but-causally-deterministic versus random-and-causally-indeterministic, will have no clearly testable and contrary implications at the level of micro-neurophysiology, even if we succeed beyond our most optimistic fantasies in mapping deliberation processes onto neural activity.

That fact does not refute libertarianism, or even discredit the motivation behind it, for what it shows once again is that we need not fear that causal indeterminism would make our lives unintelligible. There may not be compelling grounds from this quarter for favoring an indeterministic vision of the springs of our action, but if considerations from other quarters favor indeterminism, we can at least be fairly sanguine about the prospects of incorporating indeterminism into our picture of deliberation, even if we cannot yet see what point such an incorporation would have. Wiggins speaks of the cosmic unfairness of determinism, and I do not think the considerations raised here do much to allay our worries about that. Even if one embraces the sort of view I have outlined, the deterministic view of the unbranching and inexorable history of the universe can inspire terror or despair, and perhaps the libertarian is right that there is no way to allay these feelings short of a brute denial of determinism. Perhaps such a denial, and only such a denial, would permit us to make sense of the notion that our actual lives are created by us over time out of possibilities that exist in virtue of our earlier decisions, that we trace a path through a branching maze that both defines who we are and why, to some extent (if we are fortunate enough to maintain against all vicissitudes the integrity of our deliberational machinery) we are responsible for being who we are. That prospect deserves an investigation of its own. All I hope to have shown here is that it is a prospect we can and should take seriously.

For Scholars
[In Existentialism, the will condemns all the unchosen alternatives to nothingness as it grants being to the one chosen.]

Chapter 3.7 - The Ergod Chapter 4.2 - The History of Free Will
Part Three - Value Part Five - Problems