Maybe he means the fact that some people seem only to believe in the rationality that is splitting things up, decomposing everything in to units or facts instea

Maybe he means the fact that some people seem only to believe in the rationality that is splitting things up, decomposing everything in to units or facts instead of relying on intuition / the gut feeling / the indescribable knowledge you have accumulated and that is within you, and (just guessing here) thinking that the analysis you have done reaches conclusions that are indisputable, which is surely not the case, because everything you rationalize is relativistic and rooted in your view of the world, your assumptions. And on the other hand you can always know more, you have no time know all the facts, no time to weight all side of the things, except when playing tic-tac-toe. Edit: Rationalization often leads to an imbalanced position as a whole, because it's so difficult to avoid over-optimizing certain areas of your life and at the same time not neglecting other aspects of life, especially when you rely on the IDEA of how things should work out (and let's say not paying attention to what your body is signaling to you). If on the other hand you mean that it's rational to listen to your body... see where this is going...