But ideas can take on a life of their own. Few ideas are perfectly original. We borrow from all kinds of sources, often forgetting many of the latter. We ignore the original contexts and cherry-pick to suit different circumstances. That's not necessarily a bad thing--unless there happens to be nothing to add to the old idea to make it work in a different context.

The question is whether the logic of the invisible hand argument is scalable, even if Smith didn't happen to envision that it could be scaled, and even if additional assumptions must be made to extend the argument.