Description of the Symbol of the Hands Among the Manichæans
60 But why do you think it a greater crime to destroy animals than plants, although you hold that plants have a purer soul than animals? There is a compensation, we are told, when part of what is taken from the fields is given to the elect and the saints to be purified. This has already been refuted; and it has, I think, been proved sufficiently that there is no reason for saying that more of the good part is found in vegetables than in flesh. But should any one support himself by selling butcher-meat, and spend the whole profit of his business in purchasing food for your elect, and bring larger supplies for those saints than any peasant or farmer, will he not plead this compensation as a warrant for his killing animals? But there is, we are told, some other mysterious reason; for a cunning man can always find some resource in the secrets of nature when addressing unlearned people. The story, then, is that the heavenly princes who were taken from the race of darkness and bound, and have a place assigned them in this region by the Creator of the world, have animals on the earth specially belonging to them, each having those coming from his own stock and class; and they hold the slaughterers of those animals guilty, and do not allow them to leave the earth, but harass them as much as they can with pains and torments. What simple man will not be frightened by this, and, seeing nothing in the darkness shrouding these things, will not think that the fact is as described? But I will hold to my purpose, with God's help, to rebut mysterious falsehood by the plainest truth.
61. Tell me, then, if animals on land and in water come in regular succession by ordinary generation from this race of princes, since the origin of animal life is traced to the abortive births in that race—tell me, I say, whether bees and frogs, and many other creatures not sprung from sexual intercourse, may be killed with impunity. We are told they cannot. So it is not on account of their relation to certain princes that you forbid your followers to kill animals. Or if you make a general relationship to all bodies, the princes would be equally concerned about trees, which you do not require your followers to spare. You are brought back to the weak reply, that the injuries done in the case of plants are atoned for by the fruits which your followers bring to your church. For this implies that those who slaughter animals, and sell their flesh in the market, if they are your followers, and if they bring to you vegetables bought with their gains, may think nothing of the daily slaughter, and are cleared of any sin that may be in it by your repasts.
62. But if you say that, in order to expiate the slaughter, the thing must be given as food, as in the case of fruits and vegetables—which cannot be done, because the elect do not eat flesh, and so your followers must not slaughter animals,— what reply will you give in the case of thorns and weeds, which farmers destroy in clearing their fields, while they cannot bring any food to you from them? How can there be pardon for such destruction, which gives no nourishment to the saints? Perhaps you also put away any sin committed, for the benefit of the fruits and vegetables, by eating some of these. What then if the fields are plundered by locusts, mice, or rats, as we see often happen? Can your rustic follower kill these with impunity, because he sins for the good of his crops? Here you are at a loss; for you either allow your followers to kill animals, which your founder prohibited, or you forbid them to be cultivators, which he made lawful. Indeed, you sometimes go so far as to say that an usurer is more harmless than a cultivator,— you feel so much more for melons than for men. Rather than hurt the melons, you would have a man ruined as a debtor. Is this desirable and praiseworthy justice, or not rather atrocious and damnable error? Is this commendable compassion, or not rather detestable barbarity?
63. What, again, of your not abstaining yourselves from the slaughter of lice, bugs, and fleas? You think it a sufficient excuse for this to say that these are the dirt of our bodies. But this is clearly untrue of fleas and bugs; for every one knows that these animals do not come from our bodies. Besides, if you abhor sexual intercourse as much as you pretend to do, you should think those animals all the cleaner which come from our bodies without any other generation; for although they produce offspring of their own, they are not produced in ordinary generation from us. Again, if we must consider as most filthy the production of living bodies, still worse must be the production of dead bodies. There must be less harm, therefore, in killing a rat, a snake, or a scorpion, which you constantly say come from our dead bodies. But to pass over what is less plain and certain, it is a common opinion regarding bees that they come from the carcasses of oxen; so there is no harm in killing them. Or if this too is doubted, every one allows that beetles, at least, are bred in the ball of mud which they make and bury. You ought therefore to consider these animals, and others that it would be tedious to specify, more unclean than your lice; and yet you think it sinful to kill them, though it would be foolish not to kill the lice. Perhaps you hold the lice cheap because they are small. But if an animal is to be valued by its size, you must prefer a camel to a man.
64. Here we may use the gradation which often perplexed us when we were your followers. For if a flea may be killed on account of its small size, so may the fly which is bred in beans. And if this, so also may one of a little larger size, for its size at birth is even less. Then again, a bee may be killed, for its young is no larger than a fly. So on to the young of a locust, and to a locust; and then to the young of a mouse, and to a mouse. And, to cut short, it is clear we may come at last to an elephant; so that one who thinks it no sin to kill a flea, because of its small size, must allow that it would be no sin in him to kill this huge creature. But I think enough has been said of these absurdities.
Source: On the Morals of the Manichaeans (New Advent)