In the basic toolbox of any philosopher is the capacity to check the reasoning in an argument (validate a proof); the capacity to find counterexamples; and a third part which too many ‘thinkers’ lack. I call it “The Philosopher’s Eye” because it is more akin to the artist’s eye than it is to any deliberate peculiarity.
What they see could be seen by others, but it is not seen by others, because others have not fully practiced inference. In this, it is not unlike the person who first learns to draw faces. If you begin to draw faces (in an experiment which will not take more than a week to conduct) you will see faces different. You will note that perhaps you could have seen them that way all along, but that you now see them quite different. The bridge of the nose, the shape of the chin, the angle of the eyes… And if you are old enough, you will notice that what you had seen when you were drawing faces is something you may lose if you stop.
The Philosopher’s Eye could be understood like the scientists, who while studying or looking for a peculiarity, or testing a hypothesis, may literally see things others do not. But while the scientist may see things within their domain, the philosopher has no domain per se, and practiced in inference, applies that inference like the artist, everywhere.
The Philosopher’s Eye is not to be confused with the indoctrinated who cannot see things any differently than what a ‘theory’ or ‘philosophy’ tell them. Like the scientist’s eye, they are informed and on solid ground. But their foundation is on only the most general principles of logic, inference, and psychology – a solid foundation for an open mind. They can see, and quickly, to the deepest conclusions available from the surface by these basic principles. And are thereby able to quickly identify counter-examples and peculiarities which form the start of interesting theories.
Admittedly, all great thinkers do not and cannot live at all times with this Eye, less they go mad trying to reconcile all the peculiarities they have seen.