Full Idea
Electric and magnetic phenomena are profoundly intertwined; what you interpret as electric or magnetic thus depends on your own motion.
Gist of Idea
The electric and magnetic are tightly linked, and viewed according to your own motion
Source
Frank Close (Theories of Everything [2017], 3 'Light!')
Book Reference
Close,Frank: 'Theories of Everything' [Profile Books 2017], p.36
A Reaction
This sounds like an earlier version of special relativity.