„Some excuse seems necessary for the pain and loss which we occasion to brutes, by restraining them of their liberty, mutilating their bodies, and, at last, putting an end to their lives (which we suppose to be the whole of their existence), for our pleasure or conveniency.
The reasons alleged in vindication of this practice, are the following: that the several species of brutes being created to prey upon one another, affords a kind of analogy to prove that the human species were intended to feed upon them; that, if let alone, they would overrun the earth, and exclude mankind from the occupation of it; that they are requited for what they suffer at our hands, by our care and protection.
Upon which reasons I would observe, that the analogy contended for is extremely lame; since brutes have no power to support life by any other means, and since we have; for the whole human species might subsist entirely upon fruit, pulse, herbs, and roots, as many tribes of Hindoos actually do. The two other reasons may be valid reasons, as far as they go; for, no doubt, if man had been supported entirely by vegetable food, a great part of those animals which die to furnish his table, would never have lived: but they by no means justify our right over the lives of brutes to the extent in which we exercise it. What danger is there, for instance, of fish interfering with us, in the occupation of their element? or what do we contribute to their support or preservation?“
— William Paley Christian apologist, natural theologian, utilitarian 1743 - 1805
The Principles of Moral and Political Philosophy (1785), Vol. I, Book II, Ch. XI.