Post­de­ci­sional dissonance–an extremely close rel­a­tive of both post-purchase ratio­nal­i­sa­tion and the choice-supportive bias–is the phe­nom­e­non whereby once we have made a deci­sion we per­ceive our cho­sen option as the most attrac­tive choice and the dis­carded alter­na­tives as less attrac­tive, regard­less of the evidence.

Some intrigu­ing recent research sug­gests that the phys­i­cal act of clean­ing one’s hands helps us ratio­nally eval­u­ate our past deci­sions–clean­ing our hands cleans our minds, too.

After choos­ing between two alter­na­tives, peo­ple per­ceive the cho­sen alter­na­tive as more attrac­tive and the rejected alter­na­tive as less attrac­tive. This post­de­ci­sional dis­so­nance effect was elim­i­nated by clean­ing one’s hands. Going beyond prior purifi­ca­tion effects in the moral domain, phys­i­cal cleans­ing seems to more gen­er­ally remove past con­cerns, result­ing in a metaphor­i­cal “clean slate” effect.

The arti­cle is behind the Sci­ence pay­wall but there is an inter­est­ing con­ver­sa­tion in the com­ments of Over­com­ing Bias (via).