  Arguments in defense of pacifism are usually based on assertions about the immorality of violence and war. Thus pacifism is usually derived by negation. Pacifism, primarily, tells us what not to do. As Cheyney Ryan has argued, pacifism is a “skeptical position.”  As Ryan puts this: “its general claim is that the proponent of killing cannot produce a single compelling argument for why killing another person is permissible” (Ryan 1983, 509). One of the skeptical problems that Ryan addresses is the problem that occurs in killing in self-defense. When a Victim kills an Aggressor in self-defense, this killing occurs before the Aggressor has actualized his malicious intention. In this case, killing in self-defense is out of proportion to the harm done, since the Victim who kills in self-defense was not himself killed. A skeptical version of pacifism can thus develop from the worry that when we choose to kill in self-defense, we never know whether this killing is in fact justifiable.  