But, to begin with, it is surely unsound to deny that good of life to animals only because they do not appear to man to be of great account. And as for plants, we need not necessarily allow to them what we accord to the other forms of life, since they have no feeling. It is true people might be found to declare prosperity possible to the very plants: they have life, and life may bring good or evil; the plants may thrive or wither, bear or be barren. Enneads I,4,1
What, then, is the evil Soul? It is, we read, the Soul that has entered into the service of that in which soul-evil is implanted by nature, in whose service the unreasoning phase of the Soul accepts evil – unmeasure, excess and shortcoming, which bring forth licentiousness, cowardice and all other flaws of the Soul, all the states, foreign to the true nature, which set up false judgements, so that the Soul comes to name things good or evil not by their true value but by the mere test of like and dislike. Enneads I,8,4
Still, under such a dispensation, there would surely be a propriety, a reasonableness, a regard to merit which, as things are, do not appear, though this would certainly be in keeping with the noblest Providence: even though external conditions do not affect a man’s hold upon good or evil, none the less it would seem utterly unfitting that the bad should be the masters, be sovereign in the state, while honourable men are slaves: a wicked ruler may commit the most lawless acts; and in war the worst men have a free hand and perpetrate every kind of crime against their prisoners. Enneads III,2,6
Having attached all to this source, we turn to move down again in continuous division: we see the Unity fissuring, as it reaches out into Universality, and yet embracing all in one system so that with all its differentiation it is one multiple living thing – an organism in which each member executes the function of its own nature while it still has its being in that One Whole; fire burns; horse does horse work; men give, each the appropriate act of the peculiar personal quality – and upon the several particular Kinds to which each belongs follow the acts, and the good or evil of the life. Enneads III,3,1