Chemical Neurological The wisdom of repugnance has been criticized, both as an example of a fallacious appeal to emotion and for an underlying premise which seems to reject rationalism.
Although mainstream science concedes that a sense of disgust most likely evolved as a useful defense mechanism (e.g. in that it tends to prevent or prohibit potentially harmful behaviour such as inbreeding, cuckoldry, cannibalism, and coprophagia), social psychologists question whether the instinct can serve any moral or logical value when removed from the context in which it was originally acquired.
Martha Nussbaum explicitly opposes the concept of a disgust-based morality as an appropriate guide for law and policy, instead siding with John Stuart Mill's harm principle as the proper basis for limiting individual liberties, which supports the legal ideas of consent, the age of majority, privacy, and bestows equal rights unto citizens.
Nussbaum argues that the "politics of disgust" is merely an unreliable emotional reaction which has been used throughout history as a justification for persecution—racism, antisemitism, sexism, and homophobia have all been driven by popular repulsion.
For both of these reasons, I believe, anyone who cherishes the key democratic values of equality and liberty should be deeply suspicious of the appeal to those emotions in the context of law and public policy.
Consequently, citing research by Robert Putnam, Haidt argues that moral disgust and taboos may be justified in certain, culturally-specific cases wherein they can promote social capital without significantly negatively impacting the rights of many individuals, citing laws against incest (even with no risk of procreation), flag-burning, bestiality and the Armin Meiwes cannibalism case as examples:[18] [In] Lawrence v. Texas, [Justice Antonin Scalia's] dissent was that: 'If we allow homosexuality, what's next?