A framing problem rather than a single theory: the apparent tension between a universe that seems to run on cause-and-effect (or, per quantum mechanics, chance) and the near-universal human sense of authoring one’s own choices and being responsible for them. Used as the stress-test underlying every other theory in this domain.
Holds that determinism is true — every event, including every human decision, is the fixed consequence of prior causes and the laws of nature — and that this is genuinely incompatible with free will, which therefore does not exist.
Holds that free will is real and requires indeterminism to be true — that some human choices are not fully fixed by prior causes, leaving room for a person to be the genuine, undetermined origin of their own action.
Holds that only the present moment is real — the past no longer exists and the future does not yet exist — matching the common-sense view of time as a knife-edge “now” moving forward.
A proposed operational test for machine intelligence: if a human judge, conversing by text with both a machine and a person, cannot reliably tell which is which, the machine is said to have passed.
A historical rival to the Big Bang proposing the universe has no beginning or end, with matter continuously created as it expands to keep density constant.
Life arose from non-living chemistry: simple organic molecules in early Earth conditions gradually self-organized into self-replicating systems.
Holds that consciousness, or some proto-conscious property, is a fundamental and ubiquitous feature of physical reality, present in some minimal form even in basic matter.
Holds that life’s meaning and purpose derive from a transcendent creator or divine order, with human existence directed toward a further, often eternal, end.
Ancient Greco-Roman philosophy holding that meaning and a good life come from living in accordance with reason and virtue, and accepting what lies outside one’s control with equanimity.