Jonah Goldberg and Steven Haywood both find the following scientific confirmation of the "beer goggles" effect to be objectionably obvious:
A recent study at the University of Glasgow found that alcohol makes the opposite sex appear more facially attractive, at least in the eyes of the drinker. Compared to abstainers, drinkers were more likely to rate someone of the opposite sex as attractive. Alcohol had no effect on the rating of same-sex attractiveness. This may explain why drinking in bars and at parties often leads to sex.
I actually think it's an interesting finding. My hypothesis would have been that the causal mechanism was almost entirely a case of lowered standards and that something like "he looked better last night" was a pure ex post facto rationalization for past bad decision-making.
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