This is a lesson dealing with the basic justification defense of self-defense. Most of us would name self-defense as the primary justification defense; and, it is perhaps the most common or familiar of all defenses. Yet self-defense has roots in other defenses at early common law. Therefore, this lesson begins with a consideration of those roots. Moreover, there is considerable overlap between the various defenses, even when one agrees on classification. Thus, understanding the basics of self-defense is essential to understanding many or all of the justification defenses. The purpose of this lesson is to present very simply the elements of self-defense. Even a student who is just beginning the study of defenses should be comfortable working this lesson.