Why should barren couples be allowed to marry when homosexual couples cannot?

A neighbor who has PH.D. in Psychology asked me, if a homosexual couple should not be allowed to get married because they can’t procreate, then why should heteralsexual couples, knowing they can’t have children, be allowed to get married? I’m not sure how to answer him, in a way the he would accept as a PH.D., since he is not religious.

The incapacity to procreate is not the reason that homosexual couples are not allowed to marry. Marriage is a covenant between a man and a woman – not two men or two women.

For more information see:
Are gay marriages OK?
Does homosexual “marriage” hurt anybody?
Considerations Regarding Proposals to Give Legal Recognition to Unions Between Homosexual Persons

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