I'd only posit that expansion occurs because of the relaxation of a restriction. What if you don't want your single wife to make that decision for you? What if

I'd only posit that expansion occurs because of the relaxation of a restriction. What if you don't want your single wife to make that decision for you? What if you have 3 wives? I think that barring scientific evidence of the harm to 3rd parties (inbred children), govt should let consenting adults create the family they want. But that leaves the door open for sterilized cousins and siblings, and bars some current hetero marriages. Ultimately allowed marriages are a proxy for what society at large deems "reasonable." That's why this is such an issue, and I think that most arguments otherwise, on both sides, are disingenuous.