The study of what we should do and how we should lead our lives is closely connected to the study of religion. In the past, most moral philosophers assumed that the reason we have a concept of right and wrong is because God created us free but with a moral sense and wishes us to do some things and not others. Modern moral philosophers do not necessarily accept the idea of a divinely created human nature, or of absolute religious or natural laws. However, the study of applied ethics or "issues" still involves consideration of religious attitudes and the reasons for them.
Philosophers approach ethics in different ways. Some engage in descriptive ethics, surveying and describing how people behave and highlighting the characteristics of human choices and the principles we seem to follow. Some engage in meta ethics and consider the assumptions which underlie ethical discussions such as the nature of freedom, and ask whether it is possible to describe human nature and how to define commonly used words such as "good", "bad", "right" and "wrong". Other philosophers engage in normative ethics, developing systems for making decisions – ways of deciding what to do in any given situation, and it is to normative ethical systems that the majority of these notes will be devoted. Finally, there are those who engage in applied ethics, considering human dilemmas and how we should respond to them, for example questions over abortion, euthanasia, capital punishment or war.
Studying ethics usually involves some or all of the following topics:
1. Meta ethics
2. Normative ethics (systems)
3. Applied ethics (issues)
4. Descriptive ethics (which includes the study of how religion and ethics relate)