page 228 note * Note that we do not reject the aether, but only velocity with respect to the aether; that Is to say, the nature of the aether is such that it does not provide a standard with respect to which a velocity can be measured.

page 230 note * Some complication is introduced by the fact that the word “Now” may refer not to an exact instant of time, but to a period of time which, though short, is not infinitesimal. The instant in New York which is simultaneous with the instant here is indeterminate (except by arbitrary mathematical convention); but there are limits to the ambiguity, and we can fix on a period of about sec. in New York, which certainly overlaps the instant “Now” here. As we go further away the limits widen. Thus the lover who says to himself “She is thinking of me now” need not be troubled by the ambiguity, for her thought would certainly endure of a second. But if the absent one were on the planet Neptune (where the ambiguity owing to the Increased distance amounts to about four hours), he would be deprived of this consolation.