INTERACTIVE COURSE · 18 LESSONS
Logic: from arguments to evidence
A convincing conclusion is not always a justified one. Learn to tell the difference, one argument and one counterexample at a time.
What you will be able to do
Reconstruct a claim fairly, test whether the conclusion follows, build a counterexample, justify a short proof, and separate scientific evidence from an overclaim. Examples come from everyday decisions, software, and research; AI is one application, not the whole course.
Read the argument
What is being claimed, and why?
Make the structure visible
Which combinations does a rule allow?
Try to break the inference
Can the premises hold while the conclusion fails?
- 07Four similar-looking inferencesDistinguish modus ponens and modus tollens from two invalid lookalikes.
- 08Build the case that breaks itSearch systematically for true premises and a false conclusion.
- 09When the premises cannot all holdRecognize consistency, tautology, contradiction, and vacuous consequence.
Think in objects and relations
All of what? A witness for whom?
Account for every step
What permits this step, under which assumptions?
- 13A proof is a chain of permissionsJustify short natural-deduction steps using stated premises and rules.
- 14Borrow an assumption, then return itUse conditional proof without leaking temporary assumptions.
- 15Cases, contradictions, and what they proveClose every case and identify exactly which assumption a contradiction rejects.
Reason beyond certainty
What does the evidence support, and what does it leave open?
- 16Support is not entailmentSeparate deduction, induction, and causal claims without dismissing empirical evidence.
- 17Count before you trust the percentageDistinguish P(flag | defect) from P(defect | flag) using natural frequencies.
- 18A conclusion you can stand behindReconstruct, test, and qualify a real-looking argument without overstating certainty.
What this edition does not claim
This is an introduction, not a complete university logic sequence. It does not cover a full first-order proof calculus, completeness theorems, modal logic, or a full statistics course. Practice records are not a certificate, and the course has not yet been evaluated in a learner study.
Try a problem before opening its solution. A later attempt with no hints is worth revisiting after a delay, not treating as permanent mastery. Local review reminders use a simple one- or three-day interval, not a validated adaptive-learning model.
How do I retain independent judgment when using AI here?
Keep your own answer before consulting an AI candidate. Check sources, calculations, inference and conditions; explain adoption or rejection. Then solve a new-context task independently and apply the checks to this lesson.
Practice the verification workflow and keep a recordMy learning status
Mark statuses manually; visits do not establish mastery. Languages share statuses while lessons keep their own answers. This backup contains statuses only, not answers or notes.