Full Idea
All sensations are given only a posteriori, but their property of have a degree can be cognised only a priori.
Gist of Idea
Sensations are a posteriori, but that they come in degrees is known a priori
Source
Immanuel Kant (Critique of Pure Reason [1781], B218/A176)
Book Reference
Kant,Immanuel: 'Critique of Pure Reason', ed/tr. Guyer,P /Wood,A W [CUO 1998], p.295
A Reaction
Study the context to be fair to Kant, but this seems very unconvincing. If we were constructed in some more digital way, our sensations might be binary, so their 'degree' can hardly be a necessity.