Moral reasoning is a study in psychology that overlaps with moral philosophy. It is also called moral development. Prominent contributors to theory include Lawrence Kohlberg and Elliot Turiel. The term is sometimes used in a different sense: reasoning under conditions of uncertainty, such as those commonly obtained in a court of law. It is this sense that gave rise to the phrase, "To a moral certainty;" however, this sense is now seldom used outside of charges to juries.
Moral reasoning can be defined as being the process in which an individual tries to determine the difference between what is right and what is wrong in a personal situation by using logic. This is an important and often daily process that people use in an attempt to do the right thing. Every day for instance, people are faced with the dilemma of whether or not to lie in a given situation. People make this decision by reasoning the morality of the action and weighing that against its consequences.
Although all moral choice can be seen as personal choice, some choices can be seen as an economic choice, or an ethical choice described by some ethical code or regulated by ethical relationships with others.
There are four components of moral behavior. The first of these is moral sensitivity, which is "the ability to see an ethical dilemma, including how our actions will affect others." The second is moral judgment, which is "the ability to reason correctly about what 'ought' to be done in a specific situation." The third is moral motivation, which is "a personal commitment to moral action, accepting responsibility for the outcome." The fourth and final component of moral behavior is moral character, which is a "courageous persistence in spite of fatigue or temptations to take the easy way out."
Distinctions between theories of moral reasoning can be accounted for by evaluating inferences (which tend to be either deductive or inductive)based on a given set of premises.  Deductive inference reaches a conclusion that is true based on whether a given a set of premises preceding the conclusion are also true, whereas, inductive inference goes beyond information given in a set of premises to base the conclusion on provoked reflection.
This branch of psychology is concerned with how these issues are perceived by ordinary people, and so is the foundation of descriptive ethics. There are many different moral reasonings. Moral reasoning is culturally defined, and thus is difficult to apply; yet human relationships define our existence and thus defy cultural boundaries.
Lawrence Kohlberg 
Lawrence Kohlberg is a psychologist who has made significant contributions to the field of moral reasoning by creating a theory of moral development. His theory is a "widely accepted theory that provides the basis for empirical evidence on the influence of human decision making on ethical behavior." In Lawrence Kohlberg’s view, moral development comprises of the growth of less egocentric and more impartial modes of reasoning on more complicated matters. He believed that the objective of moral education is the reinforcement of children to grow from one stage to an upper stage. Dilemma was a critical tool that he emphasized that children should be presented with; yet also, the knowledge for children to cooperate. According to his theory, people pass through three main stages of moral development as they grow from early childhood to adulthood. These are preconventional morality, conventional morality, and postconventional morality. Each of these is subdivided into two levels.
The first stage in the preconventional level is obedience and punishment. In this stage people, usually young children, avoid certain behaviors only because of the fear of punishment, not because they see them as wrong. The second stage in the preconventional level is called individualism and exchange: in this stage people make moral decisions based on what best serves their needs.
The third stage is part of the conventional morality level and is called interpersonal relationships. In this stage one tries to conform to what is considered moral by the society that they live in, attempting to be seen by peers as a good person. The fourth stage is also in the conventional morality level and is called maintaining social order. This stage focuses on a view of society as a whole and following the laws and rules of that society.
The fifth stage is a part of the postconventional level and is called social contract and individual rights. In this stage people begin to consider differing ideas about morality in other people and feel that rules and laws should be agreed on by the members of a society. The sixth and final stage of moral development, the second in the postconventional level, is called universal principles. At this stage people begin to develop their ideas of universal moral principles and will consider them the right thing to do regardless of what the laws of a society are.
Jean Piaget 
Another psychologist who contributed to the field of moral reasoning was Jean Piaget. He developed two phases of moral development, one common among children and the other common among adults. The first is known as the Heteronomous Phase. This phase, more common among children, is characterized by the idea that rules come from authority figures in one's life such as parents, teachers, and God. It also involves the idea that rules are permanent no matter what. Thirdly, this phase of moral development includes the belief that "naughty" behavior must always be punished and that the punishment will be proportional.
The second phase in Piaget's theory of moral development is referred to as the Autonomous Phase. This phase is more common after one has matured and is no longer a child. In this phase people begin to view the intentions behind actions as more important than their consequences. For instance, if a person who is driving swerves in order to not hit a dog and then knocks over a road sign, adults are likely to be less angry at the person than if he or she had done it on purpose just for fun. Even though the outcome is the same, people are more forgiving because of the good intention of saving the dog. This phase also includes the idea that people have different morals and that morality is not necessarily universal. People in the Autonomous Phase also believe rules may be broken under certain circumstances. For instance, Rosa Parks broke the law by refusing to give up her seat on a bus, which was against the law but something many people consider moral nonetheless. In this phase people also stop believing in the idea of immanent justice.
Jonathan Haidt 
Jonathan Haidt is a social psychologist who defines moral as: the sudden appearance in consciousness of a moral judgment,including an affective valence (good–bad, like–dislike), without any awareness of having gone through steps of searching, weighing evidence,or inferring a moral conclusion. Moral intuition is therefore the psychological process that the Scottish philosophers talked about, aprocess akin to aesthetic judgment. One sees or hears about an event and one instantly feels approval or disapproval.  Haidt argues that many people do not utilize conscious reasoning to make our judgements.
Moral reasoning in philosophy 
Philosopher David Hume and psychologist Jonathan Haidt both claim that morality is based more on perceptions than on logical reasoning. This means that people's morality is based more on their emotions and feelings than on a logical analysis of any given situation. Hume regards morals as linked to passion, love, happiness, and other emotions and therefore not based on reason. Haidt agrees, arguing that reasoning concerning a moral situation or idea follows an initial intuition. Haidt's fundamental stance on moral reasoning is that "moral intuitions (including moral emotions) come first and directly cause moral judgments"; he characterizes a moral intuition as "the sudden appearance in consciousness of a moral judgment, including an affective valence (good-bad, like-dislike), without any conscious awareness of having gone through steps of searching, weighing evidence, or inferring a conclusion".
Immanuel Kant had a radically different view of morality. In his view, there are universal laws of morality that no one should ever break regardless of emotions. He proposed a four-step system to find out whether something was moral based on logic and reason. The first step of this method involves formulating "a maxim capturing your reason for an action". In the second step, one "frame[s] it as a universal principle for all rational agents". The third step is assessing "whether a world based on this universal principle is conceivable". If it is, then the fourth step is asking oneself "whether [one] would will the maxim to be a principle in this world". Basically what this means is that if everyone made this moral decision would it be good for the world or bad for the world. For instance, when deciding whether or not to lie to someone for one's own advantage, imagine if everyone in the world always successfully lied. Would that be good or bad for the world? Based on this logic, Kant would argue that no one should ever lie under any circumstances. Another example would be if trying to decide whether suicide is moral or immoral; imagine if everyone committed suicide. Since mass international suicide would not be a good thing, the act of suicide is immoral.
Moral reasoning and gender 
At one time psychologists believed that men and women have different moral values and reasoning. This was based on the idea that men and women often think differently and would react to moral dilemmas in different ways. Some researchers hypothesized that women would favor care reasoning, meaning that they would consider issues of need and sacrifice, while men would be more inclined to favor fairness and rights, which is known as justice reasoning. However, some also knew that men and women simply face different moral dilemmas on a day-to-day basis and that might be the reason for the perceived difference in their moral reasoning. With these two ideas in mind, researchers decided to do their experiments based on moral dilemmas that both men and women face regularly. To reduce situational differences and discern how both genders use reason in their moral judgments, they therefore ran the tests on parenting situations, since both genders can be involved in child rearing. The research showed that women and men use the same form of moral reasoning as one another and the only difference is the moral dilemmas they find themselves in on a day-to-day basis. When it came to moral decisions both men and women would be faced with, they often chose the same solution as being the moral choice. This shows that gender division in terms of morality does not actually exist. Reasoning between genders is the same in moral decisions.
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