The Two Guards, Two Doors Riddle

UPDATE: Thank you for all the great comments, and taking time to watch this. Just wanted to clear up something. You can't ask a second question. Sorry if that wasn't clear! So you can't ask something to determine the liar, and then ask the honest guard for the correct portal. Also, you don't know how the guards are assigned to the portals, so knowing which one lies doesn't determine which portal you take. Thank you for visiting. I'll create more riddle videos in the future. :)

So I decided to make a short video based on one of my favorite riddles, the famous Two Guards / Two Doors (also known as Knights and Knaves), though I used portals in this version. Labyrinth and Doctor Who also featured this. There are different ways to word the question, and another approach that still accounts for both guards. I wanted to keep things simple, but deeper explanations are out there. Hopefully someone will dig it and even *gasp* subscribe. I'm still trying to build my little channel on here ... Lol.

[WestFactor]

Hello, everyone! I'm sorry that I haven't replied to comments in such a long time. I always enjoyed the discussion. Unfortunately, life took a very difficult turn, and this channel went dormant as a result. But I would like to catch up very soon, and possibly even post new content. I never thought that people would actually watch this video when I created it, lol. In my replies to many older comments, I delve into the logic of the riddle itself, things I would clarify in my presentation, and the artistic side of making the video. I hope to give similar engagement with new viewers. One thing to remember about this riddle: You can't assume that the liar is guarding the death portal. So when you ask a simple question to determine if the guard is a liar, you still can't be sure which exit to take. Thanks for watching!

[NXeta]

Classic problem, but one thing to note though is that this answer assumes that the truth teller knows the other guard is a liar, and vice versa

[The_Azure_]

Thank you Yu-Gi-Oh for always making me remember that depending on who tells me the information for the riddle, I may have already been lied to.

[WyattRatliff-ksip]

*Kills the first guy*
"IS HE DEAD?"
"no"
"THIS ONE'S THE LIAR"

[kyleyoung]

The key to understanding how this problem is solved is understanding that by asking a guard what the other one would say, you're basically filtering the answer through one liar and one truth-teller. You're guaranteeing that you're being lied to once and only once.

[veljaatte]

you could ask one of the guards ''what door would the other guard say leads to paradise?'' in that case both guards will point the door that leads to death so you can pick the other door

[alphabulblax]

The guards look a lot funnier if you imagine those are giant mouths instead of hoods.

[dogle]

"This sentence is false. Am I correct?" And as I tear a hole in reality, I walk away from both of the doors and live the rest of my life in peace.

[MachMaelstrom]

"If I were here yesterday and I asked you which door I should take, which door would you have pointed to?"

*Truth Guard*: Points to the correct door.
*Lying Guard*: Knows he would point to the wrong door, so he'd lie about which one he would point to. Points to the correct door.

[dummydummy]

_“Am I talking to you right now?”_



The Liar: 😨 “Uhhhh, no....”

[aldinlewis]

This is a neat twist to the classic, "one of us lies, and the other tells the truth" riddle. That said I find it funny that people missed the goal of the riddle, it doesn't matter if you know who tells the truth the goal is to find the right door. (Personally I couldn't think of an answer, but it's 2 in the morning for me so I'll give myself a pass)

[FOONlX]

assuming each guard is assigned to a gate, you can ask "does the liar's gate lead to death"
"Yes" means go through that gate, "No" means go through the other gate, 4 scenarios below

S1: You ask the liar guarding the death gate - he lies and says "No" so you go through the other gate
S2: You ask the liar guarding the paradise gate - he lies and says "Yes" so you go through his gate
S3: You ask the truth teller guarding the death gate - he truthfully and says "No" so you go through the other gate
S4: You ask the truth teller guarding the paradise gate - he truthfully says "Yes" so you go through his gate

[thepuglord]

Kill one and ask the other “Is he dead?”

[notqndrew]

Ask “What color is your hood?”.
If you ask:
The Truthful Guard: Red
The Liar: A color other than red

[Vesh_in_prison]

Punches first guard: “did I just punch him?”

[narelleruddock]

You don't understand how long it took me to figure this out 🤣

[synlion]

What color is my shirt?
Truth Guy: Brown
Liar Guy: "Something else than the color of my shirt."

[novahspins]

what if you ask one guard: "is the guard in front of the death door a liar?"

if you ask a truthful guard that's in front of the paradise door, he'll say YES. if you ask a liar guard that's in front of the paradise door he'll say YES

if you ask a truthful guard in front of the death door, he'll say NO. if you ask a liar guard in front of the death door, he'll say NO.

So if you get the answer YES, you go through the door of that guard. If you get the answer NO, you go through the door of the other guard

[oldscoolgaming]

This riddle is pretty tricky, but I know how to solve it.

Simply ask "If I were to asked the other guard which door is the correct door, what would he say?" Then choose the opposite of the answer he gives you.

Here's how it works:

The Lying guard would lie to you and say that the honest guard would choose the wrong door.

The Honest guard would tell you that the liar would choose the wrong door because that's the truth.

[dasaen]

I would ask them, are you a guard? if one says no he is a filthy liar