Full Idea
None of the senses tells us that there are other senses. None of the senses tells us how the sensations it gives are related to those that are given by the other senses.
Gist of Idea
Senses are unaware of each other, and give isolated information
Source
Simone Weil (Lect 1: Materialist Viewpoint [1933], p.43)
A Reaction
That is quite striking, but it is obviously a mistake (even a category error) to think that the senses should in themselves be aware of anything. This helps to clarify their role. So we don't just know something by seeing it.
Book Reference
Weil,Simone: 'Lectures on Philosophy' [CUP 1978], p.43