Well redsox is "basically right" in principle (other than calling what should be called "assumptions" "facts"); I think part of the problem is with the original question, where we haven't defined what constitutes a "good argument."
Is an argument against gay marriage only good if it's in keeping with one of the assumptions the country was founded on, that all men are created equal? If we take that stance, then I think we can safely say none of the arguments red sox posted as examples are good, because they do nothing to address the inequality present in denying a group of people the same rights as everyone else.
But ultimately, it's an issue of practicality; I may agree with your premise, and so may another 80% of the board (perhaps we even agree that it's obvious), but unless you explain your reasoning you're not really going to convince anyone who isn't already convinced.
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No I'm not a damn furry. Looney Tunes are different. - Guiga
I wanted Sonic/Shadow romance at that time, not sex. - MWE