Full Idea
At the quantum scale there are no cats; at scales appropriate for astrophysics there are no mountains.
Gist of Idea
There are no cats in quantum theory, and no mountains in astrophysics
Source
J Ladyman / D Ross (Every Thing Must Go [2007], 4.2)
Book Reference
Ladyman,J/Ross,D: 'Every Thing Must Go' [OUP 2007], p.199
A Reaction
I don't find this convincing. Since cats are made of quantised entities, they do exist in that world, but are of little interest when trying to understand it. Similarly, astrophysicists hardly deny the existence of mountains!
Related Idea
Idea 14944 There is no single view of individuals, because different sciences operate on different scales [Ladyman/Ross]