Is morality objective? · Quiz question 33/35

Morals Left by Evolution

Evolutionary Debunking Arguments (The Darwinian Dilemma)

If "betrayal is bad" is a feeling evolution gave us to cooperate, can it be an objective fact? Sharon Street's Darwinian Dilemma and evolutionary debunking.

As it appears in the quiz

One explanation says humans needed cooperation to survive, so evolution gave us the feeling that "betrayal is bad".

If so, "betrayal is bad" is less an objective fact and more a feeling evolution left us with.

Who came up with it

American philosopher Sharon Street laid it out in her 2006 paper "A Darwinian Dilemma for Realist Theories of Value." Evolution heavily shaped our evaluative tendencies. So the realist has to say either that evolution steered us toward moral truth (scientifically unsupported) or that it had nothing to do with it (then getting it right would be a wild coincidence). Neither is good. Richard Joyce made a similar debunking argument in The Evolution of Morality (2006).

Original papers & key readings

What it's really asking

If you agreed, you think an explanation of where moral judgments come from undercuts their authority. Evolution selects for tendencies that helped survival and reproduction, not for true beliefs. "Look after your family" and "punish traitors" would have helped our ancestors whether or not they're true.

Realists respond in several ways. Derek Parfit held that moral truths can be grasped by reasoning, like math, and that the general reasoning ability evolution gave us can reach them. Another reply is the "third factor" strategy: if what helps survival (avoiding pain, cooperating) overlaps with what's actually good, evolution brought us near the truth systematically, not by luck. Many also note that the evolutionary story may be true, but getting from there to "so morality is an illusion" needs extra premises.

Where philosophers stand

Evolutionary debunking (agrees)

If moral feelings exist because they were adaptive, we have no reason to think they track independent moral facts.

Key names: Street (constructivist), Joyce (error theorist), J. L. Mackie

Non-naturalist realism (disagrees)

Just as evolved reasoning lets us know math, it lets us know moral truths.

Key names: Derek Parfit, David Enoch

Naturalist realism (disagrees)

What helps survival and what's good overlap a lot. Evolution could lead us near the truth.

Key names: David Copp, William FitzPatrick

Philosophers to check out

Sources