1. The British Medical Association says that allowing organs to be traded would put pressure on poorer people to sell.Well.. yes, and allowing cars to be traded probably puts pressure on poorer people to sell. I have no idea why this is supposed to be a bad thing. Does the BMA have some reason to believe that poorer people would prefer having two functioning kidneys to money? That they should prefer this? Is there any particular reason we should believe the BMA is likely to have anything interesting to say about the question (they're medics, not economists or ethicists)
2. There are alternatives to a trade in organs. Countries in which people's consent to donating their organs is assumed unless they opt out have shorter waiting lists.Again, I have no idea why anyone would think this was an argument against allowing a trade in organs. Countries in which a trade in organs is allowed (ie, Iran) have even shorter waiting lists (ie, they don't have any).
There are alternatives to most things, the question is which alternative is best. (I would think presumed consent is even more of a slam-dunk than allowing trade in organs, except there's remarkably little evidence that it actually increases donations).
3. Legalising the trade in organs would turn the human body into a commodity. That is taking free markets too far.To paraphrase "If we legalised trade in organs, then trade in organs would be legal. This is bad. Ner ner ner ner". This just doesn't even begin to be an argument against anything.
I'm not very surprised that the Economist agrees with me about legalising trade in organs, but surely they could have tried a bit harder to come up with some argument against? Or is it just that there aren't any?