Logical Construct & Philosophy vs Cléo

Logical Construct is an educational puzzle app that makes formal logic genuinely playable. Instead of passively reading about reasoning, you actively construct valid proofs by applying the same inference rules used by logicians, mathematicians, and philosophers: Modus Ponens, Modus Tollens, Hypothetical Syllogism, Reductio ad Absurdum, and more. Each puzzle gives you a few premises and a target conclusion. Your job is to build a chain of deductions, one rule at a time, until you reach the conclusion. By doing the proofs yourself, not just reading about them, abstract logical concepts become concrete, intuitive skills. You'll progress through propositional logic, work with modal operators of necessity (□) and possibility (◇), and tackle advanced techniques like Conditional Proof and Reductio ad Absurdum. Classic philosophical arguments (the Paradox of Omnipotence, the Problem of Evil, Anselm's Ontological Argument, and Plantinga's modal version of it) become living frameworks for applying these principles. Reasoning that shaped two millennia of philosophy, now something you can practise on your phone. WHAT'S INSIDE • 20 levels, 60 puzzles, from your first Modus Ponens to S5 modal logic • 24 inference rules organised into six categories: conditional, conjunction, disjunction, negation, biconditional, and modal • Step-by-step solution viewer that reveals the proof one move at a time: it shows you the path, it doesn't solve it for you • Truth tables for every propositional rule, with the row where all premises are true highlighted so you can see why the rule is valid • Live formula highlighting that shows which lines a rule will use • Subproofs with Fitch-style indentation: the natural way to learn Conditional Proof and Reductio ad Absurdum • First-launch tutorial that walks you through your very first deduction, plus dedicated intros for subproofs and modal logic • Atom legend on every puzzle: tap to see what each symbol stands for and read the puzzle as a story in plain language • Neumorphic design with colour-coded rule categories • Progress tracking with automatic level unlocking WHO IT'S FOR Students strengthening their formal reasoning, philosophy enthusiasts curious about how arguments actually work, or anyone who enjoys a good puzzle that makes you think clearly. - Privacy Policy: https://sites.google.com/view/logicalconstructapp/accueil - Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Reading sheet music isn't a gift. It's a skill built from short, repeated doses, and Cléo cuts it into two-minute lessons, playable standing on a train, with no instrument and no gear. WHAT YOU'LL BE ABLE TO DO • Read any note, in treble clef and bass clef alike • Recognise durations: whole, half, quarter and eighth notes, dots and ties • Understand rests, and why silence gets written down • Decode a bar: bar lines, time signatures, accidentals and key signatures WE EXPLAIN THE WHY Most apps drill rules. Cléo tells you where they come from: why a notehead is hollow or filled, why a stem flips direction halfway up the staff, why a second clef exists at all. A rule you understand doesn't need revising, it sticks. REAL SCORES, TO SIGHT-READ At the end of the second chapter, a catalogue opens: Beethoven's Ode to Joy, Greensleeves, Au clair de la lune, Frère Jacques, public domain, written as they are. The melody is shown in full and read note by note, with no sound played before the end: a note heard along the way would turn reading into dictation. It's the one gesture no exercise teaches, since an exercise always announces what it's asking for. ALREADY READ MUSIC? A short placement test finds what you already know and opens the chapter where it stops being obvious. And a chapter test lets you clear a whole chapter at once, without working through its lessons. WHAT CLÉO DOESN'T DO Cléo never listens to you play and never asks for microphone access. That's not an oversight: the app is built for the five minutes you spend waiting on a platform, and nobody sings a note in a train carriage. Everything is done by tapping, one-handed. THE COURSE IS FREE All chapters, all lessons and every exercise, with no exceptions. The optional subscription removes ads, gives unlimited lives and opens the whole score catalogue — it unlocks no lesson. Without a subscription, one score of your choice stays free. No account, no server. Your progress stays on your phone. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Terms of Service: https://cleo.eyland.app/en/terms.html Privacy Policy: https://cleo.eyland.app/en/privacy.html