Critical Reasoning Basics: Key Terminology Explained

1. Argument

An argument consists of a set of statements, where one statement (the conclusion) is supported by one or more other statements (the premises).

Example:

• Premise: All humans need oxygen to survive.
• Premise: John is a human.
• Conclusion: Therefore, John needs oxygen to survive.

2. Premise

A statement or fact that provides support or evidence for a conclusion. Premises are the foundation of an argument.

Example:

• The sun rises in the east. (Premise)
• It is morning. (Premise)
• Therefore, the sun has risen. (Conclusion)

3. Conclusion

The main point or claim that the argument is trying to establish. It is supported by the premises.

Tip: Look for conclusion indicators like “therefore,” “thus,” “hence,” “so,” and “consequently.”

Example:

• Premise: Exercise improves cardiovascular health.
• Conclusion: Therefore, regular exercise leads to a healthier heart.

4. Assumption

A hidden or unstated premise that is necessary for the conclusion to hold true.

Example:

• Premise: Sarah bought a raincoat.
• Conclusion: It must be raining.
• Assumption: People only buy raincoats when it rains.

5. Inference

A logical conclusion drawn from given information. Inferences do not always have to be explicitly stated.

Example:

• Premise: Mark was seen carrying an umbrella and wearing a raincoat.
• Possible inference: It might be raining.

6. Strengthening an Argument

Providing additional information that supports the premises and reinforces the conclusion.

Example:

• Premise: Eating fruits improves immunity.
• Strengthening Statement: A recent study found that people who eat fruits daily are 40% less likely to fall sick.

7. Weakening an Argument

Providing information that undermines the premises or conclusion.

Example:

• Premise: Drinking coffee increases productivity.
• Weakening Statement: Studies show that excessive coffee consumption leads to anxiety and reduced focus.

8. Validity

An argument is valid if the conclusion logically follows from the premises, regardless of whether the premises are true or false.

Example:

• Premise: All cats can fly.
• Premise: Tom is a cat.
• Conclusion: Tom can fly.
• (The argument is valid but not true because the premises are false.)

9. Soundness

An argument is sound if it is both valid and its premises are true.

Example:

• Premise: All mammals have a backbone.
• Premise: A dog is a mammal.
• Conclusion: Therefore, a dog has a backbone.
• (This argument is valid and sound because both premises are true.)

10. Fallacy

A logical flaw or mistake in reasoning that weakens an argument.

Example:

• Ad Hominem: Attacking the person instead of the argument.
  • “You can’t trust his opinion on climate change; he failed his science class.”

Conclusion

Understanding these critical reasoning terms will help you analyze arguments, identify flaws, and improve logical thinking. Start practicing by evaluating arguments in everyday situations and identifying their premises, conclusions, and assumptions!