"We too, through lack of knowledge and of sufficiently mature reflection, mistook the visible outward appearance of the phenomenon for the phenomenon itself"

This quote by Leon Jouhaux talks to the suggestion that we usually error the surface area level of a sensation for the phenomenon itself. This results from our lack of expertise and our failure to show deeply on the matter. Jouhaux is recommending that we frequently take the surface area level of a phenomenon and assume that is all there is to it, without taking the time to look much deeper and also recognize the underlying intricacies. This is a typical error that a lot of us make, as well as it can cause a misunderstanding of the sensation. Jouhaux is encouraging us to take the time to show deeply and acquire a far better understanding of the sensation, rather than just approving the surface area degree. By doing this, we can obtain a more thorough understanding of the sensation and its complexities.