Sacred Haven of Debauchery

And what if you've already developed your mind? Then you need to develop your muscles!

There is no limit to perfection.

The more professional literature I read, the more I am convinced that I don't know anything.

Every profession requires intelligence; those who don't use it are bad workers.

The question here is slightly different. There is rational thinking, and then there is just... knowledge.
Of course, in every profession, you need to use your mind. But the amount of information absorbed by default should be greater in non-physical work.