Full Idea
Judgments of necessity seem always to be based on thought experiments and appeals to what we can imagine.
Gist of Idea
We seem to base necessities on thought experiments and imagination
Source
Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1)
Book Reference
Sidelle,Alan: 'Necessity, Essence and Individuation' [Cornell 1989], p.1
A Reaction
That is, the denial of this thing seems inconceivable. I would say that they are also based on coherence. The idea that we can think without imagination is nonsense.