Can critical thinking be used for moral reasoning? Or maybe critical thinking and moral thinking aren’t compatible? As a matter of fact moral reasoning often use rules of formal logic to make specific conclusions. And if we consider logical thinking as one of critical thinking skills, we can say that moral reasoning uses tools from critical thinking.
But first let’s define what moral reasoning is. It is a process of making a decision or conclusion using moral principles. And a moral principle is value judgment that is general in nature. Often moral principles are based on several major perspectives, or these principles can be elements of said perspectives.
Consequentialism is focused on the consequences of a decision, so if an action produces better consequences that the alternatives it is a morally better action. One of the versions of this perspective is utilitarianism. From this point of view agents should maximize utility of their actions and actions with higher utility can be considered good. But these are disagreements between proponents of utilitarianism how to measure utility, how to define it, and how to apply this concept to human society.
Another major perspective is deontologism. This perspective considers moral duty of agents, that can be found if one consider using possible decisions as universal law that everyone should follow. For example, if a person considers stealing, the universalization would be everyone can steal. As it probably be bad for our society, the individual act of stealing also should be considered bad.
Yet another popular positions are moral relativism and moral subjectivism. The first one is the idea that perception of right and wrong depends on one’s group culture. The second one is that it depends on individual’s subjective opinion.
Another concept similar to moral relativism is religious relativism, in this case religion defines what is right or wrong. A variety of this is a religious absolutism, when one considers only a specific religion as the sole source of moral principles.
Finally one of the less universal perspectives is a virtue ethics, when one makes decisions and conclusions based on traits of character. For example if a person considers himself truthful, he would avoid telling lies.
Back to making moral decisions and conclusions. When a person needs to make a conclusion he usually takes a general maxim from one of moral perspectives like “harming others is bad” and apply it to the specific situation: “I don’t like John.” The conclusion would be “I will not harm John even if I don’t like him.” And the reasoning behind the maxim depends on a specific moral perspective, it could be a cultural thing, or utilitarian calculation, or something else.
Of course these logical steps can have errors, so you can use critical thinking to find them. You can also better understand all steps of moral reasoning if you critically evaluate the whole process.
You can find more about critical thinking and moral reasoning here: Critical thinking 10th ed. BN Moore, R Parker, N Rosenstand, 2012.