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Moral Reasoning, Legal Reasoning, Aesthetic Reasoning
Moral Reasoning, Legal Reasoning, Aesthetic Reasoning
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Reason is applying critical thinking and conscious thought to establish and verify evidence, based on either new or existing information. Reason is the method by which critical thinkers can determine cause and effect relationships, analyze the validity of arguments, engage in metacognition, and understand the relationships between concepts, objects or ideas. There are a number of different kinds of reason, each one able to be utilized for various needs.

This article will focus more of the specific methods of reason that are available to the critical thinker, as well as the situations that warrant the application of a specific method of inquiry and understanding.

Syllogistic reasoning

Syllogistic reasoning is a kind of deductive reasoning method. This method of reasoning arrives from exploring pairs of premises. Syllogisms are inferences that are drawn from two premises, each one comprised of a single quantifier. The general formula of a syllogism is as follows:

All 1 are 2 (abbreviated A)

Some 1 are 2 (abbreviated B)

No 1 are 2 (abbreviated C)

Therefore, some 1 are not 2 (abbreviated D)

In other words, a syllogism consists of three parts:

  1. General, or universal, statement
  2. Example
  3. Conclusion

However, syllogisms tend to be applied incorrectly, and can lead to false conclusions. One example is the following:

  1. All monkeys are primates
  2. Some primates have tattoos
  3. Therefore, some monkeys have tattoos

This is clearly a false statement, even if it follows the "logic" correctly.

Conditional Reasoning

Conditional reasoning is based on an "if A then B" statement. That is, B is true if A is true. However, if A is false, B can be either true or false, depending on the argument. In an "if A then B" statement, A is known as the antecedent and B is known as the consequent. In other words, what follows "if" is known as the antecedent, and what "then" is known as the consequent.

Conditional statement are described as necessary or sufficient conditions. What we call A is said to be sufficient for something else, or B, under the condition of A's occurrence being needed for the occurrence of B. In other words, the antecedent (A) is the sufficient condition for the consequent (B).

B is considered to be the necessary conditions for A whenever A cannot occur without B also occurring. Therefore, the consequent is a necessary condition for the occurrence of the antecedent.

To summarize: the antecedent is the sufficient condition for the consequent, and the consequent is the necessary condition for the antecedent.

You can diagram conditional statement.

Take this example:

If I eat too much chocolate, I will gain weight.

To begin diagramming this conditional statement, you can use letters to represent the antecedent and consequent.

EC can be substituted for "eat too much chocolate", and GW can be substituted for "will gain weight."

Therefore, you can write the conditional statement as follows:


The contrapositive of a conditional statement is tantamount logically to the original conditional, but provides a different perspective to the statement. You can determine the contrapositive statement by switching the consequence and the antecedent. After doing this, you negate each term:

GW → ~EC

The contrapositive statement will therefore now read: If I do not gain weight, then I did not eat too much chocolate."

If the conditional is true, the contrapositive is also true.

Moral Reasoning

Moral reasoning has to do with determining whether a particular behavior or idea is right or wrong. To determine whether or not something is right or wrong, it is necessary to first determine what the intended act is. You must know what is desired to be accomplished, what the accomplished state will be, etc.

However, this is not enough. You must also consider whether or not the intended or desired consequences are good for yourself, for those around you, the environment, etc.

The major principle used in moral reasoning is as follows: "What is good for all of humanity?"

Moral reasoning arguments are determined utilizing the above principle. Any behaviors or ideas are examined with its relationship to all of humanity and how the consequences of the behaviors or ideas would affect all of humanity.

There is a general structure to moral arguments. One premise of a moral argument will state the general moral principle, and a second premise will state the facts or claims. The conclusion then states a derivative moral judgment. This structure to moral arguments is deductive: since the general moral principle is true, and the facts and claims applies the moral criterion to the general moral principle, then the conclusion must be accepted as being true. The general formula of a moral argument is as follows:

(1) Any action having properties A, B, C . . . is right (or wrong).
(2) This action has properties A, B, C.
This action is right (or wrong).

Aesthetic Reasoning

Aesthetic reasoning is utilized to debate about art. The process is used to defend the judgments, or to criticize, judgments about art. Aesthetic reasoning is usually engaged in using the following eight principles:

  1. Objects are aesthetically valuable if they have meaning or teach something valid
  2. Objects are aesthetically valuable if they express the values of the cultures they are made in, or express the artists who make them.
  3. Objects are aesthetically valuable if they can lead to social change or the positive fulfillment of a social ideal.
  4. Objects are aesthetically valuable if they give their audience pleasure.
  5. Objects are aesthetically valuable if they give their audience certain emotions, or evoke certain thoughts and feelings in a given audience.
  6. Objects are aesthetically valuable if they produce a certain experience that comes from the art itself, such as suspending disbelief.
  7. Objects are aesthetically valuable if they possess a special property.
  8. Objects are aesthetically valuable because they have certain features that no reason can be applied to them:
    1. This principle corresponds to moral subjectivism: There's nothing to say in reasoned discourse about tastes.

Hypothetico-Deductive Reasoning

The hypothetico-deductive reasoning model is the one most known as the scientific method's inquiry process. A hypothesis is determined via empirical data, tests are then done to either prove or disprove the hypothesis.

The basic formula for this type of reasoning is as follows:

  1. Use observations and experience; data is gathered and previous explanations are explored for answers. If the problem is new and no evidence is available, proceed to step two:
  2. Formulate a hypothesis, meaning, try to explain a certain aspect of the observation in question.
  3. Predict from the hypothesis: if you assume x is true, what consequences do you determine from that premise?
  4. Test: look for evidence that conflict with the prediction.


Satisficing is a decision-making skill in which alternatives are determined before an acceptability mark is met. This sort of reasoning is performed when optimal solutions cannot be found. Satisficing provides an understanding of the tendency to select the first option that meets a given need, or selecting the option that seems to address a certain need the most, rather than trying to find an optimal solution. This sort of reasoning warrants an awareness; this is where metacognition comes into play. It is necessary to recognize a given situation and environment, where the optimal solution is not available to us, and we therefore go along with the first thing that seems to work well enough. There is no exact formula for awareness; rather, self-reflection and metacognition will be necessary that the solution chosen is not just chosen because it happens to be "good enough."

Fallacious Reasoning

A fallacy is an error in reasoning which prevents the reasons provided accepting a certain conclusion from providing any real support for the claim that the conclusion is true. In other words, a fallacious argument seems to offer valid reasons for accepting a conclusion as being valid and true, but closer examination indicates that the argument is not valid. In essence, a fallacy is an error in reasoning. There are a number of different kinds of fallacies; some of the major ones will be covered in this chapter.

Fallacies fall in one of two broad categories:

  1. Fallacies of relevance: occur when the point is missed, and a premise fails to support the conclusion logically
  2. Fallacies of ambiguity: occur when the meaning or definition of a term shifts, so the terms do not match up with the argument

We will explore several fallacies here:

  1. Appeal to inappropriate authority: this fallacy occurs when the authority figure or institution being called upon do not truly have any legitimate hand in the matter. In legal writing, this fallacy occurs when an authority from a case or from another jurisdiction beyond the one being worked on is called upon as the authority figure. This fallacy may also occur when the opinion of an expert is cited, even if the matter is outside their area of expertise.
  2. Irrelevant conclusion: this fallacy occurs when the premises "miss the point" and fail to support the conclusion. Rather, the premises support each other, or some unstated conclusion. This fallacy is typically used when a particular objective is argued for, but offer generalized support for that objective when that support could also support an alternative approach. An irrelevant conclusion is also known as a non sequitur.
  3. False cause: this fallacy is based on treating something as a cause that is not, or should not be considered to be, a cause. Usually, the mistake follows the following formula:

the mistake is in assuming that A caused B simply because A preceded B.

  1. Overzealous application of a general rule: this fallacy occurs when generalization is applied to a case that it does not govern. The mistake often occurs when failing to recognize that there may be exceptions to a general rule.
  2. Hasty generalization: this fallacy is the mirror of the one above. It occurs when we try to apply or establish a broad principle or general rule based on very specific observations.
  3. Circular reasoning: this fallacy occurs when the truth of what you are seeking is assumed to be true before every effort is used to prove it. In other words, an argument is circular when the conclusion is part of the premises used to reach that very same conclusion. This is also known as begging the question. These kinds of fallacies are sometimes easy to miss because they superficially sound good. Essentially, an argument is circular when it assumes the very thing it is setting out to try to prove.
  4. Complex question: this fallacy occurs when the question is phrased in such a way that it presupposes the truth of a conclusion buried in that question. The solution to this is to divide the question so that they can be answered separately, before a general conclusion is reached.
  5. Ambiguity: this type of logical fallacy uses a key word or phrase to have more than one different meaning in the same single argument.
  6. Composition: In this fallacy, the characteristics of the part of a whole are applied to the whole.
  7. Division: this fallacy is the opposite of the fallacy of composition. That is, in the division fallacy, the attributes of the whole is substituted for the attributes of the parts. In other words, the characteristics of the whole are applied to the parts.
  8. Argument from ignorance: This fallacy maintains that a proposition is true because it has not been proved false, or that it is false because it has not been proved true.
  9. Ad hominem: this fallacy is also known as the "attack the person" fallacy. It occurs when the argument is directed at the person who asserts a conclusion, rather than at the conclusion itself.
  10. Argument from force: this fallacy substitutes subtle threats for persuasion, or it asserts that something must be the case because "that's just the way things are".
  11. Appeal to emotion: this fallacy occurs when emotionally charged language is used in place of logical argumentative language.
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