I think GP is saying that the people who choose to work directly as philosophers, mathematicians, scientists, and doctors and the people who choose to take the

I think GP is saying that the people who choose to work directly as philosophers, mathematicians, scientists, and doctors and the people who choose to take the risk of hiring other philosophers, mathematicians, scientists, and doctors for some greater endeavor have importantly different skill sets, nevermind if the risk taker is a philosopher, mathematician, scientist, or doctor themself.