When thinking about the topic of free will and moral responsibility, it’s critically important that you keep your concepts straight and not allow yourself to jump from one idea to another too quickly. So here are three distinct issues–phrased as three yes/no questions. (Note that this is slightly different from but closely related to the version in W07 Slide #22 because the post was originally written for a different cohort.)

  • Is the universe causally deterministic?
  • Is free will compatible with determinism?
  • Does moral responsibility require free will?

In principle, you can answer either “yes” or “no” to each without reference to the others.

  • Is the universe causally deterministic?

Is it true that “absolutely everything that happens–your actions and decisions included–is causally determined to happen exactly as it does by what has already gone before”? If you answer “yes”, then you opt for Determinism; and if you answer “no”, then you opt for Indeterminism. (Note: Indeterminism doesn’t say that absolutely everything is not causally determined; all it says is that at least some things are not causally determined by what has already gone before.)

  • Is free will compatible with determinism?

Is it the case that you can both have free will and the universe also be causally deterministic? Or does one exclude the other? If you answer “yes”–they are compatible, then you opt for Compatibilism; and if you answer “no”, then you opt for Incompatibilism. (Note: Saying that two things are compatible–or incompatible–doesn’t mean you actually think that either of the two actually exists. You are just saying that they can, or cannot, exist together.)

  • Does moral responsibility require free will?

Is a capacity for free will a necessary condition for our being morally responsible creatures? Is our exercising free will a necessary condition for our action and decision to be something for which we can be morally responsible? Assuming that, by free will, you mean the ability to do otherwise, saying “yes” to this question means you agree with the Principle of Alternate Possibilities (PAP). In contrast, saying “no” means that you reject that principle, and this is the position of Semi-Compatibilism. (In W07, I also called the PAP the “Free Will Doctrine”.)

Since there are three yes/no questions, there are a total of eight logically possible combinations. But not all of the combinations are attractive or commonly occupied. I’ll go through the main ones below. Please note that you don’t need to know any of the below positions by heart–if we mention one of them in the quiz or exam, we will define the position for you.

  • Soft Determinism = Determinism + Compatibilism + Principle of Alternate Possibilities

On this combination, we can be moral responsible for our actions and decisions–because we can still exercise free will despite determinism. Historically, it’s a standard position for someone who believes both that the universe is deterministic, and that we can be morally responsible.

  • Hard Determinism = Determinism + Incompatibilism + Principle of Alternate Possibilities

On this combination, we can’t be morally responsible for our actions and decisions. It’s a standard position for someone who believes the universe is deterministic and because of that, we can’t really be morally responsible. We might think we are morally responsible; but that’s only because we are confused or deluded.

  • Libertarianism = Indeterminism + Incompatibilism + Principle of Alternate Possibilities

On this combination, we can be moral responsible for our actions and decisions. It’s the standard position for someone who believes we are or can be morally responsible because we have the sort of Free Will those existence implies that the universe is indeterministic.

As you can see, all of the above hold fix the idea Principle of Alternate Possibilities. What if that’s the one that is given up? As previously mentioned, we get this:

  • Semi-Compatibilism (= reject Principle of Alternate Possibilities)

On this position, moral responsibility is itself compatible with determinism. If you reject the Principle of Alternate Possibilities, then it is usually the case that you don’t have as much of a stake in the Compatibilism vs. Incompatibilism debate. Why is that? Because that debate centers around whether free will is possible given our conception of the universe. If we care about free will mainly because we care about moral responsibility, and it also turns out that moral responsibility doesn’t require free will, then we don’t have a lot of reason to worry about whether, given a deterministic conception of the universe, we are morally responsible. But other than that, Semi-Compatibilists are essentially allies of the Compatibilist–in that both attempt to argue that we can have moral responsibility even if the universe is deterministic. And if the Semi-Compatibilist also happens to be a Determinist, her position becomes a close by cousin of Soft-Determinism.

Incidentally, most recent philosophers who have a broadly Compatibilist outlook probably tend towards Semi-Compatibilism, rather than the older, more “Classical” position of Compatibilism. One style of argument for Semi-Compatibilism is associated with Harry Frankfurt’s (in)famous thought experiments–widely called the “Frankfurt Cases” in the literature. The jury is not exactly settled on the soundness of Frankfurt’s arguments, and attempting to refute or defend the “Frankfurt cases” became a bit of a minor cottage industry.

But there are also other important proposals (including some that also came from or were inspired by Frankfurt). Somewhere in the mix is the idea that maybe what we need for moral responsibility is something like a capacity to act in response to reasons; and such a capacity can plausibly be shown to be compatible with Determinism. This sort of view, best associated with John Martin Fischer and Mark Ravizza, is currently regarded by many working in the area as “the gold standard for cutting edge defenses of compatibilism”.

Slightly different even though still related are accounts that draw strength from a seminal article by P. F. Strawson (that’s Galen’s father, mind you) titled “Freedom and Resentment,” and the best contender in this direction is probably the account advanced by Jay Wallace. I’ll confess to being partial to the Wallace way of thinking, but that’s a different story for another time.

One final bit–not sure if you noticed but Galen Strawson doesn’t belong straightforwardly in the above classification. His big idea is that moral responsibility is an incoherent idea (because it involves an infinite regress)–and this is meant to hold whether you think Determinism or Indeterminism, Compatibilism or Incompatibilism is true.