There are plenty of arguments that use reason in regards to the homosexual debate. First, physiologically, males don’t fit together. A male wasn’t designed to accept something in an orifice in the behind. Females don’t fit together. Second, The whole sexual process from arousal to completion is all about procreation: The woman accepting the sperm of the man. Third, there are two observable purposes of sexual intercourse: procreation and unity. To use sexual intercourse outside these two purposes flows against their creative purpose. Homosexual sex can unify the couple, but that unity cannot produce children. Thus, the act is disordered. Fourth, sociologically speaking, it is better for a child to grow up in a home with both a male and female parent that love each other. They learn about what it means to be a male from their father and what it means to be a female from their mother. They learn about the opposite gender as well.

Don’t agree with you Mark on the sex = procreation debate. We weren’t designed to swim, doesn’t mean we can’t!! But it doesn’t make swimming a sin?
Does this mean that people too old to have children shouldn’t get married? or that people who are not straight and fertile are surplus to requirements? I’m assuming you must be straight and fertile yourself? Just a thought.