Moral reasoning is your use of logic in deciding such moral questions as What would be right? What would be wrong? What is the lesser of two evils? Moral reasoning is strongly influenced by prevailing cultural values and norms guiding what we should or should not do. Should our actions benefit the culture, or solely ourselves? Moral values are culturally defined, thus criteria used in moral reasoning vary widely across the globe.
Moral choices are also strongly influenced by religious doctrine. Some religions promise perfect and everlasting celestial bliss as reward for living a morally ‘good’ life. Purgatory, a ‘lake of fire’, or eternal damnation is promised for immoral or unethical actions. Many nonbelievers, however, have only secular motivations for their moral reasoning, and expect no ultimate reward for their moral actions.
In making moral judgments, you employ four aspects of your psyche. Moral sensitivity is your ability to anticipate how your actions might affect others. Moral motivation is your commitment to taking moral action. Moral judgment is your ability to reason correctly about what 'ought' to be done in a specific situation. Moral character is your desire to choose the most moral action, and to be accountable for the results of that choice.
Compassion and altruism are programmed into the human genetic code by DNA. Moral and ethical reasoning, and its resultant human behavior, are also programmed by DNA. ‘Good’ actions have tended to preserve life, thereby promoting genetic fitness and perpetuating the species.