Full Idea
If there is nothing which commands immediate respect through reason, such as the basic rights of man, no influence can prevail upon man's arbitrary will and restrain his freedom.
Gist of Idea
There can be no restraints on freedom if reason does not reveal some basic rights
Source
Immanuel Kant (True in Theory, but not in Practice [1792], 2-Concl)
Book Reference
Kant,Immanuel: 'Political Writings', ed/tr. Reiss,Hans [CUP 1996], p.86
A Reaction
I think this is the nearest Kant gets to natural rights. It is hard to see how basic rights can be identified by pure reason, without some inbuilt human values. Kant's usual move is to say denial of them leads to a contradiction, but I'm going off that.