Possibly originating with Greek philosopher Epicurus, Hume summarizes Epicarus' version of the problem of evil as follows: "Is God willing to prevent evil, but not able? Then he is not omnipotent. Is he able, but not willing? Then he is malevolent. Is he both able and willing? Then from whence comes evil?" The logical problem from evil is as follows: P1. If an omnipotent, omnibenevolent, and omniscient god exists, then evil does not. P2. There is evil in the world. C1. Therefore, an omnipotent, omnibenevolent, and omniscient god does not exist. This argument is in the form modus tollens: If the premise (P1) is true, the conclusion (C1) follows of necessity. To show that the first premise is plausible, subsequent versions tend to expand it, such as this modern example: P1a. God exists. P1b. God is omnipotent, omnibenevolent, and omniscient. P1c. An omnipotent being has the power to prevent that evil from coming into existence. P1d.  An omnibenevolent being would want to p...

 A broad concept of evil defines it as any and all pain and suffering, yet according to John Kemp, evil cannot be correctly understood on "a simple hedonic scale on which pleasure appears as a plus, and pain as a minus." According to the National Institute of Medicine, pain is essential to survival: "Without pain, the world would be an impossibly dangerous place." Marcus Singer says that a usable definition of evil must be based on the knowledge that: "If something is really evil, it can't be necessary, and if it is really necessary, it can't be evil." The narrow concept of evil involves moral condemnation, and is applicable only to moral agents capable of making independent decisions, and their actions. Philosopher Eve Gerrard suggests that evil does not describe ordinary wrongdoing, and that "there is a qualitative and not merely a quantitative difference between evil acts and other wrongful ones; evil acts are not just very bad or wrongful ...