sense of mutual justice, which, in their intercourse with one another, ought to be as operative as law, and the energies of which are essential to the happiness of society.
XXI.
Because whenever the number and hostility of predatory land animals might so tend to prevent the cultivation of vegetable food, as to render it indispensible to destroy them in self-defence, there could even in that case exist no necessity to destroy the animated existences in water; and, as in most civilized countries there exist no land-animals besides those which are purposely bred for slaughter or luxury, of course all destruction in such countries must arise either from unthinking wantonness or carnivorous gluttony.
XXII.
Because the stomachs of locomotive beings appear to have been provided for the purpose of conveying about, with the moving animal, nutritive substances, analogous in effect to the soil in which are fixed the roots of plants; and, consequently, nothing ought to be introduced6
