This is mainly directed at libertarians, but why is slavery to which the enslaved has consented wrong? Should it be allowed? I can already anticipate most of the replies involving the invalidation of contracts that infringe upon rights, but so long as the contract is agreed to by both parties, what's wrong with it? Keep in mind that current laws aren't a sufficient basis for argument. You cannot say that such a contract would be invalid simply because it involves an unlawful act, because the idea is to determine whether or not the act is truly unlawful.