Final answer:
Determinism posits that all events are wholly determined by preceding causes, while compatibilism holds that moral responsibility and free will are compatible with determinism.
Step-by-step explanation:
Determinism is the philosophical view that all events are determined completely by previously existing causes. Under determinism, every event has a cause, and free action and moral responsibility are seen as impossible by hard determinists.
In contrast, compatibilism (or soft determinism) is the view that the kind of freedom necessary for moral responsibility is consistent with the truth of determinism. Compatibilists argue that we can still act as free, morally responsible agents when, in the absence of external constraints, our actions are caused by our desires.
The only "grade" of free will that is compatible with determinism, according to compatibilism, is a version of free will that considers actions free if they are not externally constrained or impeded, even if they arise from antecedent conditions that render no other behavior possible.
This form of free will does not assert that humans possess ultimate free will but rather that their voluntary behavior, even if causally determined, can still be considered free in the sense that it aligns with the individual's desires and intentions. This reconciliation allows for moral culpability under a deterministic framework since individuals act according to their own will.
Criticisms of compatibilism often emerge from hard determinists who argue that redefining freedom to align with deterministic principles undermines the concept of true freedom of choice. Nonetheless, compatibilists hold that, to maintain a sense of accountability and moral responsibility, this redefinition is necessary and coherent.