Jamieson, Fausset and Brown on Daniel 7:3

3. beasts--not living animals, as the cherubic four in Re 4:7 (for the original is a different word from "beasts," and ought to be there translated, living animals). The cherubic living animals represent redeemed man, combining in himself the highest forms of animal life. But the "beasts" here represent the world powers, in their beast-like, grovelling character. It is on the fundamental harmony between nature and spirit, between the three kingdoms of nature, history, and revelation, that Scripture symbolism rests. The selection of symbols is not arbitrary, but based on the essence of things.