Logic Problems? Logic Solutions: ir/iational

It tastes like oxygen?

A good understanding of the logic of logic seems like something that should be taught in schools. Along with tax returns, how to fight a bear, and English punctuation. As discovered by Eurogamer’s Ellie Gibson this week, ir/rational is a game that broaches the thought through topic of logic in a – strange way.

But it doesn’t really go far enough.

It’s a fantastic concept. A game in which you’re not looking for the solution to the puzzles – it gives you those. But rather you must prove that the answer is correct. To do this you embrace the precise world of logic, specifically propositional calculus. For instance,

IF John is sexy
AND sexiness causes smooches
THEN John receives smooches
John IS sexy
THEREFORE John receives sexy, sexy smooches

Your goal, in increasingly tricky puzzles, is to select the correct path through the logic using the drop-down menus. All with the motivation of escaping a room. It’s nicely presented, with witty silliness all around the puzzles, and a decent ending too. But my frustration is that it doesn’t go far enough. It really only teaches that one routine really, and goes no deeper. And as someone who doesn’t really understand any of it, I was quite hoping to learn. Oddly the most interesting moment – questioning some logic of the existence of a perfect God – comes right at the start, and it never goes any further than that. At no point do you really get into the complexities of true and false statements, and their impact on other statements. But, by the end, you will have accidentally learned the shorthand language used by Propisitionalcalculusologists, and perhaps it’s good not to have gone too far down the bleak alley of proving that A is A.

But, blimey, take a look. It’s the first truly logical adventure game I’ve ever played.


  1. caddyB says:

    I pretty much do this for a living in the university and I love this game.

    • Sheng-ji says:

      Most days, I feel like I have to do this for a living :/ The game does look interesting and fun

  2. Akimbo says:

    Erm, Adam, two weeks ago.

    • Coccyx says:

      Does nobody read RPS any more? link to rockpapershotgun.com

      • Dervish says:

        I’ll tell you what the problem is. That one used a frou-frou colorful bunny picture as the header.

        I think John is excused.

        • kansashi11 says:

          A lot of the sale of the Super Speed ​​USB 3.0 Multi Memory Card Reader! Wholesale link to lnko.in

        • rei says:

          I remember ignoring the story based on that picture, so you’re correct in at least my case.

          *you hear gas seeping into the room*

    • Faldrath says:

      IF John had read Adam’s article THEN he would not have posted this one.
      John posted this one.
      THEREFORE John did not read Adam’s article.

      Modus tollens, go!

      • eclipse mattaru says:

        Hey, leave the man alone. If it means having my pictures up at RPS twice in one week, they can keep Alzheimer-posting as much as they want :D

    • SlappyBag says:

      Erm, like, 3 years ago?

      link to rockpapershotgun.com

      (I missed both so thanks for triple posting =D)

    • Phasma Felis says:

      What’s really best is that Adam’s post from two weeks ago starts off by mentioning that Alec wrote about it three years ago.

      If we can just get Jim and Nathan to write about it, we’ll have the whole set.

    • westyfield says:

      To be fair, neither Adam nor Alec before him even vaguely explained what the game is about, thus dooming it to be forgotten before I’d even closed the tab.

      • jezcentral says:

        Indeed. I must have read the reports, but I never felt the urge to play the game. Now I do.

        I would say that this proves John Walker is the better games journalist, but correlation doesn’t imply causation.

        That’s LOGIC, that is.

  3. Unaco says:

    This reminds me of another game, that was essentially 20 or so problems in propositional calculus. Can’t remember what it would have been called, vaguely remember it was about confusing/fixing an AI or similar… Can’t remember if I saw it here, or somewhere else.

    Edit: Coccyx’s link just above, goes to this game from a few weeks ago… and lo, the game I’m thinking of was the original of this, which RPS wrote about 2 1/2 years ago. It was ir/rational I was thinking of then, by Tom Jubert, from Penumbra fame.

    link to rockpapershotgun.com

    • Coccyx says:

      Now we just need Jim Rossignol to post about it and the hive mind will reach convergence.

      • The Random One says:

        Maybe that’s the game’s backstory.

      • lazer says:

        the irony of you commenting about this article being posted before when there are a series of comments directly above mentioning the precise same thing and then talking about all the writers having a go is not lost on me.

        also run-on sentences for days

        • Unaco says:

          My comment may come ‘after’ the comment above… but if you look at the time stamp, they were posted at the same time. Hence my editing to mention that Coccyx had linked to the previous article, which in turn linked to the game I was thinking of. Also, not everyone hits F5 on a page every 0.0004 seconds, as you must to keep up with all of the comments. Some of us, some times, open a couple pages maybe, and then it takes 5 minutes to get to one, and then we comment. And then realise a similar comment has been made a few minutes before our own, as we were reading other articles.

  4. Dervish says:

    What’s funny about this is that it’s not so much about understanding the logical consequences (I think most people here will find that straightforward), it’s about recognizing the odd and counter-intuitive ways some people like to try to construct their arguments. “Wait, why are they asserting THAT, and why THERE?”

  5. Fierce says:

    This is a great gaming concept, a sort of Portal for the mouse with only one button to click.

    I almost get the feeling that if this game were handled correctly, with user feedback on why wrong answers are wrong in an entertaining manner, this could almost be universally referred to as a tool to foster a more intelligent Internet of the future!

    Imagine! An Internet where comment threads contain a higher percentage of participants who understand what a logical fallacy is and actively self-correct themselves and question their position before rage-clicking the Submit button!

    Sigh, I know, I know. Still. Tread lightly, for you tread on my dreams.

  6. Krimson says:

    Your argument is faulty: We’ve established that you are sexy, but nowhere is it stated that the smooches received due to this are sexy. They might be wet, horrible smooches from a Wicked Witch.

    • The Random One says:

      Yeah, the example is invalid. “Sexiness causes smooches” should be a premise, not a conditional.

      IF RPS readers are way too smug

  7. ErrantConstruct says:

    Does page load for anyone? It seems the Newgrounds servers are melting.

  8. Post-Internet Syndrome says:

    I’m stuck on 7/10. I don’t understand what it wants me to say. “Australia is wrong to ban video games” and “Australia is wrong to ban 18+ rated games” are not the same thing, which imples I should go the park in disabled spaces route, but there is not enough statements to do that.

    • Dervish says:

      The meat of the argument is in steps 4-7 at the bottom. Your job is to add the missing links that let you get from 4 to 6.

      • Post-Internet Syndrome says:

        Yeah I can see that, and that’s what the hints tell me too, but statements seem to be missing or something. I can make 1 say that if videogames are not more dangerous than film, video games should be treated similarly to film, making 5 true. For 2 though, there is no way to make 6 true, since no statement saying banning video games is wrong exists.

        • Post-Internet Syndrome says:

          And while I was writing that I tried the arrow keys, which promptly revealed those statements, hidden outside the selection box. No scroll bar existed to imply any more options were available. Great interface design there…

          • Dervish says:

            Might be a browser issue; I had everything show up in one list with no scrolling needed when I clicked on the drop-down menus.

          • caddyB says:

            Definitely a browser issue or something. I had no problems.

          • Dominitus says:

            Definitely a browser issue – I couldn’t see the options that would allow me to solve the puzzle in Chrome. When I switched to Firefox, there they were.

          • MrPyro says:

            I just quit at the same question; the options were not appearing for me. But I was trying it on Linux so I guess I deserve it.

          • hosndosn says:

            Oh, that’s kinda lame.

  9. Mike says:

    I hadn’t noticed Adam’s post, so thanks for re-doing this John! This is pretty fascinating-looking.

    You mentioned that “Oddly the most interesting moment – questioning some logic of the existence of a perfect God – comes right at the start, and it never goes any further than that.” I think the problem is that the underlying basics of propositional logic are very repeat-y. The interesting stuff is beyond that, in places like predicate logic, so you can change A from ‘John is sexy’ to ‘The world is round’ but the same logical tools are applied in the same way.

    I think this is really strong though. This is exactly the kind of thing we need to teach kids, as you point out, and this is a really nicely-produced way of doing it. It has some problems with its wording, though – some of the arguments are poorly written and it’s hard to see where you’re supposed to be going, I think.

    I’d like to see a full game version of Natural Deduction though. The wiki page makes it look super complicated, but the right game would make it really fun.

  10. sub-program 32 says:


  11. Koozer says:

    Completely stuck on the wording of 9/10. What does it want me to say?? If it thinks smugness is a clue, and that smugness is a red herring, then (what does it want to go in here? Every combination I try to prove the contradiction fails)

    • Shiri says:

      What it wants is for you to reiterate the same line in the “THEN” as in the “THEREFORE” immediately after it.

      PROBABLY IRRELEVANT SPOILER MARK: if it thinks it’s a red herring, AND if it thinks it’s a clue, THEN it’s contradicted itself, THEREFORE it’s contradicted itself

      • Mr Labbes says:

        I actually needed a walkthrough for this, I still don’t understand why I should repeat that. Shouldn’t the “therefore” be implied in the “then”?

        • Shiri says:

          Not exactly. You do need to spell out the logical step between “A is true”, “if A is true then B”, and “in that case, B.” Some people (including me, I had to think about it for a few minutes) will get stuck precisely because we just skip ahead to the obvious conclusion, but skipping ahead is exactly what causes a lot of logic problems so I guess forcing yourself to do every step in order is part of the discipline of mental hygiene.

    • Hidden_7 says:

      This one struck me as the most poorly designed question. It’s the only one that doesn’t work in purely logical terms. That is, I was converting all the questions to symbols as I was doing them, and this is the only one that full on falls apart and doesn’t work purely symbolically.

      You’re presented with the premise that basically A->B, and then asked to prove B with that. You simply can’t, without making assumptions. At that point, just assume B and be done with it; it’s a pointless waste of time to bother assuming A first.

      What it wants you to do is recognize that semantically a red herring and a real clue are contradictory/opposites. Which is a leap of imbuing real meaning to the statements that isn’t required for other questions, and the sort of thing that usually just gets in the way of symbolic logic.

  12. Phantoon says:

    I liked how I switched the answers multiple times on #9, and the original answer I gave was the correct one, just that it didn’t accept it the first time for whatever reason.

  13. Legionary says:

    It’s interesting and fun, but because there are drop-down options it’s possible to reason your way to the correct answer by deciding which of the options it can’t be, rather than thinking about figuring out using logic which the correct one is on its own merits.

    • Shiri says:

      True, although “guess the verb” would probably be excruciatingly painful.

  14. Devan says:

    I fully support any endeavors that teach people more about formal logic. I’ll be checking this out for sure.

    Edit: It’s pretty good, although there’s a bug on one of the levels (maybe #6) where the two conclusions need to be in a particular order for you to pass. Also, the 9th puzzle has a grammar mistake in the first premise (it’s phrased as a question rather than a sentence).

  15. Melliflue says:

    It doesn’t understand contra-positives :(

    I tried using one for part 7 but it told me it was false.

    EDIT: Although it does require understanding contra-positives to solve some of the puzzles. So I guess it just doesn’t like me trying to catch it out.

  16. povu says:

    The tenth puzzle is a nasty one. I solved it by replacing the symbols with words that start with the same letter, which lead to a lot of sillyness. Uh… Spoiler? :P

    ‘Great is what I am’.
    If ‘Mom is here’, then if ‘Great is what I am’, then ‘Awesomeness occurs’
    ‘Mom is here’
    Therefor, ‘Awesomeness occurs’.

    If ‘Mom is here’, and ‘Awesome occurs’, then ‘ I am not Eccentric’
    Therefor, ‘I am not Eccentric.’

    If ‘I am Old and Vain’ then ‘I am not Eccentric or Rude’. Also if ‘I’m not Eccentric or Rude’ then ‘I’m Old and Vain’

    Therefor, I’m ‘Old and Vain’!

    Do not question my rationality.

    • Hidden_7 says:

      That’s funny, the tenth was the easiest for me, because it was already sorted. I learned symbolic logic in school, emphasis on the ‘symbolic.’ Most of the game I was converting the puzzles to symbols just as matter of course, because semantic sentences are just messy and get in the way. We’re talkin’ syntax here, people, what does meaning have to do with it?!

    • gamma says:

      I kinda surprised myself on this one, thinking that i would require more time to figure the logic. I started by memorizing the logic symbols first… and read the statements out loud to answer them in the same go.

      Next time i think to myself the “internet is wrong” in some forum, i’ll try and simply abstract the nonsense to simple “A”, “B” prepositions and see how it goes. Should be useful to reduce all the rethoric to the logic substance of any discussion.

      • Phantoon says:

        Then the joke is on you, sir!

        Most people on the internet don’t USE logic! AHAHAHAHA!

    • Simon Hawthorne says:

      That one annoyed me – when I learnt propositional calculus ‘V’ doesn’t translate easily to natural language “Or” (i.e. only one proposition can be true). I was taught that a logical “Or” operator actually means “Either or Both”; it doesn’t matter for that puzzle but grated on me nonetheless.

  17. Zerdav says:

    Game is great, but to easy, and not tested enough, as there were two possible answers in one example, while it accepted only one. Still, great fun.

  18. hypercrisis says:

    nice enough, i remember having these kind of puzzles in books as a kid. alas these have been replaced by sudoku books

  19. Igor Hardy says:

    Nice logic tests. But a series of disconnected puzzles doesn’t make an adventure game. Therefore, a truly logical adventure game has still to be made.

  20. Josh04 says:

    Um, unless you’re identifying John exactly with the concept of being sexy, then that’s first-order logic or predicate logic, which is not propositional logic at all. Even if John were the avatar of sexiness incarnate, “John is sexy” would be a statement in the meta-language, really only indicating that sexy and John are two names with the same referent rather than a logical statement.