Full Idea
Einstein noted that the measurements of space and time are not independent but inextricably linked, leading to the idea of unified space-time (introduced by his former teacher Minkowski).
Gist of Idea
Space-time arises from the connection between measurements of space and of time
Source
report of Albert Einstein (works [1915]) by Graham Farmelo - The Strangest Man 03
Book Reference
Farmelo,Graham: 'The Strangest Man [Paul Dirac]' [Faber 2009], p.40
A Reaction
Notice the instrumentalist assumptions behind this.
Related Idea
Idea 7621 Special relativity, unlike general relativity, was operationalist in spirit [Putnam on Einstein]