Full Idea
The principle of persistence is one that anticipates experience just as much as that of causality.
Gist of Idea
An a priori principle of persistence anticipates all experience
Source
Immanuel Kant (Critique of Pure Reason [1781], B795/A767)
Book Reference
Kant,Immanuel: 'Critique of Pure Reason', ed/tr. Guyer,P /Wood,A W [CUO 1998], p.657
A Reaction
This is the notion that identity is an indefinable basic of our understanding. He is objecting to Hume, who, of course, thought persistance was just an experience. Personally I persistance to be a posteriori, but how else could things exist?