Structure of claims and their relationship to truth.
Critical thinkers want to know  what is true. That’s the whole point of reasoning.  In this section you will learn what the word  “truth” means, what knowledge is and how it differs  from opinion. You will also learn how to properly  categorize sentences so you can know how to  evaluate them.

A. Properties of  claims.

Every claim has four  attributes, the first three of which  must be determined before reasoning.  The fourth attribute is determined by  reasoning.

1.Descriptive or Prescriptive claims

a Descriptive  claims  tell how the world is, was, or will  be.

1) Example:  “Bob is friendly.” This sentence  describes how the world (Bob being part  of the world) is.

2) Example:  “Texas was once a sovereign nation.”  This sentence describes how the world used to be.

b. Prescriptive  claims  tell  how the world should  be.  (This includes all possible time  frames.)

1) Example:  “You should take your doctor’s  advice.”

2) Example:  “Abortion should remain  legal.”

3) Should  means,  “There  is an overriding reason  to...”  In the first example, the person is recommending that given all possible  choices, there is a reason which is so  strong and so compelling, that all  other options must be abandoned in  favor of following the doctor’s advice.

4) Related  term:  Normative

Normative  claims are a subset of prescriptive  claims which deal with values and morality. The second example, “Abortion  should remain legal” is a normative  claim.

2. Objective  or Subjective claims

a. Objective claims have a truth value which is the same for you, for me, and for others. In other words, if a claim is true, then it is true for everybody in the world and if it is false, then it is false for everybody in the world.

1) Example:  “Milwaukee is in Wisconsin.” Whether a  person knows that this is true or not, or whether they believe it or not, the  claim actually is true for  everyone.

2) Example:  “Slavery is wrong.” If this claim is  true, then it is true for everybody.  One’s agreement with the claim is  irrelevant. Whether one owns a slave or  is a slave or lived in the antebellum  south is irrelevant. The truth value is  the same for everyone.

3) Example:  “Abortion is wrong.” The nature of this  claim is exactly like the one above.  Only the noun is changed. People  disagree about the truth of the claim,  but the claim is objective. That’s why  people argue about it. If they agree  with the claim, then they are saying,  “This claim is true for everyone, even  those who disagree with me.” Those who disagree with the claim are saying,  “This claim is false, even for those  who disagree with me.” Both of these  examples have to do with human beings  who are the same everywhere, always and  forever. This demonstrates that most  moral claims about humans are  objective.

b. Subjective  claims  are claims where the truth of the claim  can reasonably differ for you, for me,  and for others.

1) The  important thing to keep in mind is that  we’re talking about the actual truth,  not just one’s belief. Subjective  claims generally deal with preference  and taste. These are matters that are  not worth arguing about, because they  affect only the individual and no one  else.

2) Example:  “I prefer women with lots of tattoos.”  Notice that there is no logical  conflict with another person making the  opposite claim.

3) Example:  “My favorite football team is the  Packers.” It is neither right nor wrong  to have the Packers as a favorite team.  Also notice that there is nothing  logically contradictory about another  person saying, “My favorite team is the  Saints.”

3. Absolute  or Relative claims

a. Absolute  claims  are  invariant always and  forever.  In other words, if the truth of the  claim can (practically speaking) never  change with circumstances of time or  place, then it is considered  absolute.

1) Example:  “Milwaukee is in Wisconsin.” We’ve  already determined that this claim is objective. (By the way, it’s also  descriptive.) It is also absolute,  because cities don’t change location.  They pretty much stay put. So the claim  “Milwaukee is in Wisconsin ” was true  100 years ago, it was true one week  ago, it is true today, and it will be  true 100 years from today.

2) Example:  “Slavery is wrong.” Most Americans now  agree that this claim is true, though slavery is still practiced in such  places as China and the Sudan. It is  wrong because it unfairly treats humans  as property. It was just as wrong when  it was practiced in the United States  and it is wrong for the Chinese and the  Sudanese to practice it too. The reason  is that people are always the same  regardless of where they live or when  they live.

b. Relative claims are claims where the truth can change with circumstances of time and place. In other words, a claim that is true now, might be false later on.

1) Example:  “Joe is in Milwaukee Wisconsin.” People  don’t stay in one place like cities do. Joe might get on a plane and fly to San  Francisco, in which the words “Joe is  in Milwaukee Wisconsin” would become  false.

2) Example:  “It is autumn.” Utter these words every  four months. One of those times the claim will be true, the other three, it  will be false.

4. True  or False

a. Every  claim is either true or  false.  It doesn’t matter if you agree with a  claim and it doesn’t matter if you know  whether it’s true or false. It also  doesn’t matter if other people disagree about the claim.

b. Truth:  A  claim is true when it corresponds with  reality.  “Reality” covers not only the material world, but also the metaphysical,  moral, and ideological world. Take for  instance “justice.” You can’t go out to  the store and get one, but “justice” is  still real. We can make claims that are  true about justice. For instance, if an  innocent man goes to jail for a crime  he didn’t commit, while the real  criminal got away, we can truthfully  say, “Justice wasn’t done.”

c. It  isn’t always easy to see whether the  claim is true or false. That’s what  we’re trying to discover when we  reason. Before we reason we know one  thing for sure; the claim that we’re  reasoning about IS true or false. Not  both. Not neither.

Related Concept: Matters of Opinion and Matters of Fact

a. If something is a “matter of opinion,” then it is a subjective issue.

In these cases, what “matters” is the opinion and nothing else.

b. If something is a “matter of fact,” then it is a objective issue.

In these cases, what “matters” is the fact.

c. Why people get  confused.

1) People often think  that if something is controversial or  if the answer is unknown, then this  falls into the category of “matter of  opinion.” This is incorrect.

2) People can have  opinions about matters of  fact.

Example: “It is my  opinion that there is nothing wrong  with having an abortion.”

This is an  opinion about a matter of fact.  Either there is something wrong with it or there is not. It is not a  matter of personal preference as is  one’s preference for ice  cream.

Example: “It is my  opinion that people live on other  planets.”

This is an  opinion about a matter of fact.  Either people do live on other  planets or they don’t. This is not a  matter of personal preference, even  though no one knows the  answer.

B. The Three Laws of Logic

1. Law  of Identity:  If  a claim is true, then it is  true.

2. Law  of the Excluded  Middle:  Every claim is either true or  false.

3. Law  of  Non-Contradiction:  No claim can be true and false at the  same time.

C. Bringing  these concepts together.

It is  essential that you understand that EVERY  claim has exactly one attribute from EACH  of the four categories discussed. For  instance, the claim “Milwaukee is in  Wisconsin” is DESCRIPTIVE, OBJECTIVE, ABSOLUTE, and TRUE.

Helpful  tips:

If  a claim is subjective, then it is  automatically relative.

If  a claim is absolute, then it is  objective.
Caution, it does not work the other way  around. In other words, one cannot  assume that because a claim is  relative, that it is subjective or that  if a claim is objective, that it is  absolute.

No  claims are subjective and  absolute.