Full Idea
If the brutes have any ideas at all, and are not bare machines (as some would have them), we cannot deny them to have some reason.
Gist of Idea
If animals have ideas, and are not machines, they must have some reason
Source
George Berkeley (The Principles of Human Knowledge [1710], Intro §11)
Book Reference
Berkeley,George: 'The Principles of Human Knowledge etc.', ed/tr. Warnock,G.J. [Fontana 1962], p.51
A Reaction
It seems possible to imagine a low level of mind, where a few ideas (or concepts) float around, but hardly anything worth the name of reason. However, a Darwinian view suggests that concepts must bestow an advantage, so the two go together.