Full Idea
Consciousness is that power of the mind by which it has an immediate knowledge of its own operations. …Every operation of the mind is the exertion of some power of the mind.
Gist of Idea
Consciousness is the power of mind to know itself, and minds are grounded in powers
Source
Thomas Reid (Essays on Active Powers 1: Active power [1788], 1)
Book Reference
Reid,Thomas: 'Inquiry and Essays', ed/tr. Beanblossom /K.Lehrer [Hackett 1983], p.300
A Reaction
I strongly favour this account of the mind and consciousness in terms of powers, because they give the best basis for their dynamic nature, and seem to be primitives which terminate all of our explanations. Science identifies the powers for us.