Full Idea
To reply to Zeno's Arrow Paradox, Russell developed his 'at-at' theory of motion, which says that to move from A to B is to be at the intervening points at the intervening instants.
Gist of Idea
Russell's 'at-at' theory says motion is to be at the intervening points at the intervening instants
Source
report of Bertrand Russell (Human Knowledge: its scope and limits [1948]) by Stathis Psillos - Causation and Explanation §4.2
Book Reference
Psillos,Stathis: 'Causation and Explanation' [Acumen 2002], p.113
A Reaction
I wonder whether Russell's target was actually Zeno, or was it a simplified ontology of points and instants? The ontology will also need identity, to ensure it is the same thing which arrives at each point.