MegaMaester

Critical Thinking · Lesson 3

Logic and Reasoning

beginner⏱ 14 min · 8 cards
The big idea
🧩

How conclusions follow

An argument offers premises to support a conclusion. Learn to see the structure — and test it.

Three ways to reason

Pick your logic

Tap each one.

Key term

The key distinction

Valid vs. sound?
tap to reveal ↻
Valid vs. sound
Valid = the conclusion follows from the premises. Sound = valid AND the premises are actually true.
Try it

Argument Builder

Premise: All birds can fly.

Premise: A penguin is a bird.

Therefore a penguin can fly.

Your verdict:

Judge each argument: valid & sound, valid but unsound, or invalid?
Nuance

Watch out

Think like a Maester

A perfectly logical argument can still be wrong. Check the structure AND the premises.

Recap

Key takeaways

  • ✓An argument = premises offered in support of a conclusion.
  • ✓Deductive reasoning guarantees; inductive reasoning makes probable; abductive reasoning finds the best explanation.
  • ✓Validity is about structure; soundness is validity plus true premises.
  • ✓A valid argument can still be unsound if a premise is false.
Quick check

What best describes critical thinking?

Related lessons