This still doesn't prove (what RB tries to claim) that the concept of free market is atomic, that it can't be further reduced to distinct interactions of individuals (with all their whimsies and fancies) by way of deduction, on the one hand, or that it can't be arranged from the same interactions by way of induction, on the other...
As I've said, free market is a particular form of individual economic interactions taken integrally, as a whole
What can and cant be sold is determined by society (or more like the government to be specific).
In a free market scenario where the government would not be involved, the rules would still apply. Most people have morality ,not because of some laws that politicians issue, but because they have conscience.
That aside, the market is just an organized way for humans to interact and pass value around.
It's not an atomic, because the market is a collection of individuals, the market is focused on the individual, it's not a collectivist system.
And as I said earlier it's fundamentally based on 2 instincts: greed & fear.
Until humans have those traits,markets will always exist.