From Heyburn's decision, posted by the Louisville Courier-Journal:
These arguments are not those of serious people. Though it seems almost unnecessary to explain, here are the reasons why. Even assuming the state has a legitimate interest in promoting procreation, the Court fails to see, and Defendant never explains, how the exclusion of same-sex couples from marriage has any effect whatsoever on procreation among heterosexual spouses. Excluding same-sex couples from marriage does not change the number of heterosexual couples who choose to get married, the number who choose to have children, or the number of children they have.
"The state’s attempts to connect the exclusion of same-sex couples from marriage to its interest in economic stability and in 'ensuring humanity’s continued existence' are at best illogical and even bewildering," he concluded.
The state of Kentucky isn't the only entity pushing that argument, though: former Republican presidential candidate Rick Santorum said the same last month.