I'm afraid that considering the situation that so many women are in, reluctantly selling their bodies because of poverty and addiction, I think it is fair to consider exploiting them shameful, and I hope it does not become less so.

Of course. I never said I objected to the shame implicit in exploiting other people - and nor did Professor Grayling, as far as I'm aware. But that's not the same as the shame which many in society attach to the business of buying and selling sex per se, whether the person doing the selling is exploited or not. This is perhaps where the heart of the problem lies. I think there are very real problems in using the latter sort of shame as a crude palliative against the activities to which the first sort of shame attaches. That would be rather like objecting to sweat-shop labour by making the buying and selling of clothes a shameful activity.

The most significant problem is that it simply doesn't work. In fact it seems that shame has never been a spectacularly good defence against anything a society wishes to prohibit. People don't stop doing what they want to do because it is considered shameful, they just do it and feel ashamed about doing it. Usually they try to hide the fact they're doing it too, and engage in considerable hypocrisy to lend their cover story credibility. In the case of human trafficking and sex slavery, I'm not sure our society COULD put greater opprobrium upon it, and that certainly doesn't stop it happening nowadays.