Evil is discord or disturbance in the order of the universe. Leibnitz divides it into metaphysical evil, i.e., imperfection; physical evil, i.e., suffering; moral evil, i.e., sin. Origen defined evil to be the negation of good; and in this he has been followed by many Christian thinkers. The distinction into natural and moral evil is the only one now generally recognized.
1. "Natural evil is whatever destroys or any way disturbs the perfection of natural beings, such as blindness, diseases, death, etc. But as all that we call natural evil is not the penalty of sin, nor, as some have supposed, only the penalty of it, such disturbance is not necessarily an evil, inasmuch as it may be counterpoised, in the whole, with an equal if rot greater good, as in the afflictions and sufferings of good men. When such disturbance occurs as the penalty of transgression, it is the necessary consequence of moral evil." The tendency of modern thought is towards the doctrine that the (apparent) disturbances of the physical world are likely to be reconciled with universal law as science advances.
2. "Moral evil is the disagreement between the actions of a moral agent and the rule of those actions, whatever it be. Applied to choice, or acting contrary to the revealed law of God, it is termed wickedness or sin. Applied to an act contrary to a mere rule of fitness, it is called a fault" (Bucky s.v.). On the origin of evil, and its relations to the government of God, SEE SIN; SEE THEODICY.