Full Idea
To the mathematician as such there is no relevant distinction between the instants of time and the points on a line.
Gist of Idea
Mathematicians don't distinguish between instants of time and points on a line
Source
Bertrand Russell (The Principles of Mathematics [1903], §387)
Book Reference
Russell,Bertrand: 'Principles of Mathematics' [Routledge 1992], p.403
A Reaction
This is the germ of the modern view of space time, which is dictated by the mathematics, rather than by our intuitions or insights into what is actually going on.