Two Yale psychologists debate here why the culture has shifted on the question of homosexuality. They argue it's less about our better arguments than our gut response to images of gay people below the level of consciousness. Think: ick factor. My view is that the marriage and military issues have helped do this: because they gave the public images of gay people that overwhelmed the sexually-defined other in favor of the responsibility-defined friend or relative. Once that image had been shifted, the arguments could get through. Now look at the images of the San Diego rally for marriage equality last week below. This is a new world - and it's one where discrimination looks more and more unacceptable:

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