Practical Logic and Sound Arguments
Like Duolingo, but for Practical Logic and Sound Arguments. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
21 levels across 3 sections, about 42 minutes end to end, roughly 8 days at five minutes a day. It moves through Deconstructing Arguments and Problems, Diagnosing Flaws and Traps, and Building Solutions and Navigating Debate. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android

Key ideas in Practical Logic and Sound Arguments
- Rhetorical flourishes and emotive adjectives add persuasive force but carry no logical weight
- A premise must offer factual or evidential support directly bearing on the conclusion
- Removing rhetorical filler leaves the bare truth-functional claim intact
- Descriptive claims state testable or empirical conditions about reality
- Normative claims make value-laden prescriptions using words like ought, should, or must
- Deriving an ought solely from an is without a value premise commits the naturalistic fallacy
- Charity demands interpreting ambiguous phrasing in the most rational, defensible form
- Attacking an opponent's weakest reading constructs a fragile straw man rather than testing truth
- Charitable reframing pinpoints the strongest version of an objection before refuting it
- Enthymemes leave critical bridging premises unsaid because speakers assume they are obvious
- Missing premises often link an empirical observation directly to an ethical or action threshold
- Challenging an unstated assumption collapses the inferential link between premise and conclusion
- Independent premises provide parallel, redundant pathways of support to a conclusion
- Dependent premises operate as linked chains where one broken link invalidates the entire inference
- Refuting one independent premise merely lowers the overall confidence without defeating the claim
- Categories overlap when an expense item belongs to more than one branch simultaneously.
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Practical Logic and Sound Arguments the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
When someone is trying to prove a point, what job must a premise actually do?
Get it right to open this lesson and 20 more in the app.
Where Practical Logic and Sound Arguments takes you
Deconstruct complex problems, spot structural flaws in reasoning, and construct arguments that hold up under pressure. Move from intuition to rigorous, systematic thinking.
- 1
Deconstructing Arguments and Problems
- Isolating the Core Argument
- Root-Cause Problem Decomposition
- 2
Diagnosing Flaws and Traps
- Structural Validity and Formal Fallacies
- Informal Traps and Rhetorical Sleights
- 3
Building Solutions and Navigating Debate
- Designing Robust Solutions Under Uncertainty
- Dialectical Disagreement and Crux Finding
- Epistemic Calibration and Argument Quality
3 sections · 7 units · 21 levels. Built to play, not to enroll.
You pick the voice
Practical Logic and Sound Arguments is taught in the The Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
More Philosophy on Tomo
Everyday Logic: How Arguments Work
Learn to break everyday arguments down to their real bones, spot flawed reasoning before you get misled, and construct points that hold up under pressure.
The Philosopher's Toolkit
Move beyond basic definitions to master the mechanics of logic, the nuances of ethical decision-making, and the structures of human knowledge.
Theology and the Big Questions
Explore the intersection of faith and logic. Learn to build rock-solid arguments using the wisdom of Aristotle and Aquinas while mastering the art of metaphysical debate.
Thinking Clearly: Tools from Philosophy
Stop just having opinions and start building arguments. Learn the mental tools philosophers use to dismantle bad logic and make better decisions every day.
Philosophy for Clearer Thinking
Move beyond basic definitions to master the frameworks that shape how we argue, live, and understand reality. Learn to dismantle weak logic and build a coherent worldview.
Thinking Like a Philosopher
Learn to question everyday assumptions, untangle confusing arguments, and navigate tough moral choices. Discover how philosophy works as a practical toolkit for living with greater clarity.
Start Practical Logic and Sound Arguments today.
Download Tomo, search Practical Logic and Sound Arguments, and play your first lesson in under a minute.