It simply proves that there are sensations and sensations, and that certain of these are better and more precise than others.

The visual sensation of relation in space seems to be _par excellence_ the scientific sensation which it is sought to substitute for all the rest.

But, after all, it is but a sensation.
Let us recognise that there is, in all this contempt on the part of physicists for sensation, only differences in language, and that a paraphrase would suffice to correct them without leaving any trace.

Be it so.

But something graver remains.