My theory logically starts with the right to life. A friend asked me, 'What is the right to life?' and I didn't know well enough to answer her. So I want to think about that here.
A Right -- A right is an intangible; it is an idea. It is an idea governing human inter-action. Further, it is an idea which causes some inter-actions to be deemed unjustified. Unjustified actions infringing on a person's life would violate a person's right to life.
Let's take a second to think about what rights a person has or ought to have. Autonomy and equality are important in understanding this. In Western society, it is a common belief that Random-Citizen-A is not qualified to command Random-Citizen-B to believe X. It is up to individuals to decide what they want to believe. People decide for themselves. Additionally, it is generally believed that every person in the world is unjustified in demanding that Random-Citizens-A or B believe X. This is because each person's mind is not to be governed by another. Each of us is autonomous because we are equal.
Right to Life -- As we are autonomous and equal, the right to life is seen when we realize that, just as no one else can rightfully impose his or her beliefs on another, no one can justifiably impose harm on another (except under certain circumstances which I hope to explore later). The unprovoked killing of someone would violate his or her right to life because this would be acting in a way that denies his or her autonomy and equality.
