Brutes compare but imperfectly.
How far brutes partake in this faculty, is not easy to determine.

I imagine they have it not in any great degree, for, though they probably have several ideas distinct enough, yet it seems to me to be the prerogative of human understanding, when it has sufficiently distinguished any ideas, so as to perceive them to be perfectly different, and so consequently two, to cast about and consider in what circumstances they are capable to be compared.

And therefore, I think, beasts compare not their ideas further than some sensible circumstances annexed to the objects themselves.

The other power of comparing, which may be observed in men, belonging to general ideas, and useful only to abstract reasonings, we may probably conjecture beasts have not.
6.

Compounding.
The next operation we may observe in the mind about its ideas is COMPOSITION; whereby it puts together several of those simple ones it has received from sensation and reflection, and combines them into complex ones.