Sometimes I have a hard time keeping track of just what the different positions in the free will debate are. To help clarify a little, I offer the following map of the terrain. I'm interested to hear whether this seems like an appropriate breakdown.
The basic terminology will be 'compatibilism' and 'incompatibilism', but I think it's important to be clear about what thesis is supposedly compatible or incompatible with what other thesis. To that end, I think there should be three different compatibility questions -- 1) Is determinism compatible with the ability to do otherwise?, 2) Is determinism compatible with moral responsibility?, and 3) Is indeterminism compatible with moral responsibility? There's also a fourth question that's not about compatibility, but which seems equally important, namely: 4) Does moral responsibility require the ability to do otherwise?
Call someone who answers (1) with a 'Yes' an APCompatibilist and someone who answers (1) with a 'No' an APIncompatibilist. Call someone who answers (2) with a 'Yes' a D-MRCompatibilist and someone who answers (2) with a 'No' a D-MRIncompatibilist. Call someone who answers (3) with a 'Yes' an I-MRCompatibilist and someone who answers (3) with a 'No' an I-MRIncompatibilist. Finally, call someone who answers (4) with a 'Yes' a PAPist and someone who answers (4) with a 'No' a PAP-denier. Now, with these positions staked out, we can start to see the different combinations and how they map onto the views people actually hold.
"Official" semi-compatibilism = D-MRCompatibilist + I-MRCompatibilist + PAP-denial
Fischer's version of semi-compatibilism = APIncompatibilist + D-MRCompatibilist + I-MRCompatibilist + PAP-denial
Pereboom's view = APIncompatibilist + D-MRIncompatibilist + I-MRIncompatibilist + PAPist
"Traditional" compatibilism (local-miracle, altered-past, conditional-analysis) = APCompatibilist
Galen Strawson's view = D-MRIncompatibilist + I-MRIncompatibilist (because MR is impossible!)
Kane's and van Inwagen's view = APincompatibilist + D-MRIncompatibilist + I-MRCompatibilist (event-causation) + PAPist.
O'Connor's and Clarke's (former) view = APIncompatibilist + D-MRIncompatibilist + I-MRCompatibilist (agent-causation) + PAPist
Ginet's and Goetz's view = APIncompatibilist + D-MRIncompatibilist + I-MRCompatibilist (no causation) + PAPist
I'm sure I'm missing some view here, so please feel free to chime in. Now, another interesting question is: What views should we associate with labels like 'Source Incompatibilism' and 'Leeway Incompatibilism' and 'Libertarianism' and 'Hard Determinism'? Here is what I'm inclined to do:
Source Incompatibilism = (AT LEAST) D-MRIncompatibilist (because of sourcehood concerns)
Leeway Incompatibilism = APIncompatibilist and PAPist, THEREFORE D-MRIncompatibilist.
Libertarianism = (AT LEAST) D-MRIncompatibilist, and I-MRCompatibilist (whether no cause, event-cause, or agent-cause) -- and by the way, we are morally responsible,so determinism is false.
Hard Determinism = D-MRIncompatibilist -- and by the way, determinism is true, so we're not MR.
At least, that's what I'm inclined to say about these views to begin with. But you'll notice that even this fails to distinguish between, say, hard determinists about the ability to do otherwise and hard determinists about MR, or between libertarians about the ability to do otherwise and libertarians about MR. Also, this way of mapping things out doesn't really lend itself to seeing the connections between different parts of a view, and that is what sometimes makes a view distinctive. I tried to capture that by using 'therefore' in Leeway Incompatibilism, but I'm sure there are some other connections this map doesn't pick up on.
I'm not sure what all this shows (except maybe that our terminology is really messy!), but I hope it is a way of gaining a bit of clarity on the situation. Suggestions and amendments welcome.