Because you ask so nicely...because you post in such good faith...because irony is wasted on you, I'll tell you this much: your introducing the word "bad" here as a gloss on the expression "an argument against" indicates that you are thinking in political buzzwords on this topic, and suggests that my argument is over your head...
Well thank you, and since you're so civil, I'll refrain from pointing out your grammatical error.
You don't know what irony is, do you Baldrick?
Yes I do, it's like goldie and steely but made of iron.
...human marriage, is unjustifiable in evolutionary terms, and absent any other terms of justification, is unnatural and otiose. And that means marriage between man and woman, man and man, woman and woman, and between any of the billion genders politics has invented to the consternation of rationality wherever it still exists.
Then you do not know what evolution is.
It is the process to refer to biological changes in a species over time. Evolution does not say what changes would be beneficial or not.
Furthermore evolution doesn't change a species to its optimum level - merely one to which the species can successfully breed and survive.
You appear to be saying that human population would be bigger if marriage didn't exist. So what???
The human population is if anything too big.
Marriage hardly prevents homo sapiens from surviving and successfully breeding.
QED; The institution of marriage is NOT an impediment to the survival of the species.
Was that over you head?
...any spark of understanding yet?
Do you now understand the evolution theory better?
It is not to argue that changes occur, we know changes occur, it is to explanin how and why they occur, not to suggest ways of improvement.
So with that put to bed.
Are there any good, non-religious arguments against same sex marriage?