Being a person with some sympathies for some aspects of libertarianism in economics, I have always been prone to resist the application of the word 'exploitation'. For years I probably would have said that I didn't believe there was such a thing as exploitation as some separate natural kind of wrong, that whenever there was a real wrong done that got labeled in that way, it could be analyzed into some other category--trying to induce someone to do something wrong, for example, exercising coercion, or engaging in fraud. And I am still unlikely to agree with a lot of people who use the word frequently, especially about wages. I'm probably going to say that some of the things they want to label with that word are not even wrong, much less instances of exploitation.
But I now do believe that there is such a thing as exploitation.
I'm a great believer in the use of the paradigm case in ethics, and I think a paradigm case of exploitation is that of Westerners who are now traveling to third-world countries to buy kidneys. Even if we grant that there are instances where a live kidney donation can be perfectly morally legitimate, buying a kidney is a different matter altogether, and there are excellent reasons why it is illegal in the U.S. Moreover, it makes it worse (and this is why it's an instance of exploitation) that the kidneys are being purchased from poor people who wouldn't give up a kidney at all if they didn't really need the money.
But I'm still not at all sure what exploitation is. The nub of my puzzlement is this question: Can we give any further overarching account of why some things--especially services or actions--should not be for sale? In the case of sex, we're on very solid ground in terms of the function, and for Christians, the God-ordained intent of sex in uniting one man and one woman. But one can hardly say that kidney donation has a created function. The activity is entirely man-invented, and no one had ever heard of such a thing two hundred years ago.
So here's a thought experiment to get us going in trying to decide what it is about certain things--specific heroic acts, perhaps?--that makes it the case that they must be done out of love, charity, or good-will rather than being sold: Suppose that a small child falls into a narrow well or hole of some sort and can't be gotten out in any ordinary way. The rescuers are becoming desperate when they hear of a midget in the neighborhood who is so small that he has a chance of being able to get down into the well to rescue the child. Let's say that the odds of his not only succeeding but getting back alive and without permanent major injury are neither very good nor very bad. Let's say it's 60 to 40 odds that all will be well. But that's still a pretty big risk for him to take. From here the scenario diverges into two sub-scenarios. In A, the rescuers and parents simply go to the man's house, put the situation before him, and ask him if he would be willing to help. In B, the rescuers and parents, learning that he is extremely poor and has eight children, offer him a huge sum of money, to be given even for the attempt, that will go either to him if he survives or to his family if he dies.
What's wrong with B? Clearly, there's nothing wrong with A. That must mean that it isn't wrong in itself for the man to help, or it would be wrong to ask him to help. In fact, it would be heroic for him to help. But B seems, to me at least, like an attempt at exploitation. The idea seems to be that his poverty is being used to pressure him to take a large risk out of a desire to help his family when he would not take that risk simply out of concern for the trapped child. But why is that wrong?