A silly logical question...

[Candlelight]

I was searching around and i found this logical question worded in a silly way...however, it's kinda hard (at least for me, don't have an answer yet) to solve, so i wonder what your answers will be? Anyways, it goes a little something like this:

________________________________________________________________________________________________________________________________________

Someone ate my cabbage soup (sounds a bit silly, but stick with me here). There are four suspects: Steve, James, Dave & Tyler. Each suspect can say two statements about the "crime", a true one and a false one.And so the "interrogation" begins...

Steve says: "I didn't eat it. Either it was James or none of us did it."

James says: "I didn't eat it either. Tyler did it."

Dave says: "Neither did I. James is lying when he said that Tyler ate it."

Tyler says: "I only eat meat. If Steve didn't do it, James did it."

Now the question remains, who of these four is the mysterious soup thief?

________________________________________________________________________________________________________________________________________

Please post your answers and the logic behind them! I'm curious...

Edited December 18, 2016 by Candlelight
title edit

[Superfluous J]

Tyler's first statement is semi-ambiguous. If true, he couldn't have eaten the soup but if false, he only may have eaten it.

The simplest statements are James', he said he didn't do it, and Tyler did. If his first statement is true then Tyler didn't eat it either, but we learn nothing about Tyler's 2nd statement's veracity by this.

If James DID do it, though, both of his statements are lies. Therefore, we can guarantee he didn't do it, and Tyler also didn't do it.

The next easiest statements are Dave's. We've already established that James lied when he said Tyler did it, so Dave's second statement is true. Therefore, we can conclude that Dave's first statement is false and therefore he did it.

Therefore we can conclude that Tyler does in fact only eat meat (the truth) as his second statement is the false one.

And finally Steve, his first statement is true so his second statement (if it wasn't james, it was nobody) is false. As we know it was Dave, this fits the logic.

Therefore "Dave ate your soup" fits what everybody said, based on the 1 lie, 1 truth idea.

Edited December 18, 2016 by 5thHorseman
Fixed my ancilary logic and wording

[stibbons]

My answer:

Spoiler

Dave ate the soup.

And here's my reasoning:

Spoiler

If James had eaten the soup, then both of his statements would be lies. So he didn't eat it - his first statement about not eating the soup is true, which means that his statement blaming Tyler for eating the soup is a lie (coincidentally clearing Tyler).

That means Dave is telling the truth when he said James is lying about Tyler. So Dave must be lying when he says he didn't eat it.

 

[LordFerret]

I don't care for borscht, so as far as I'm concerned they can all share it.

[LN400]

Reasoning

Spoiler

T means true, L means lie.

Assume Steve ate it: 

Steve says: "I didn't eat it (L). Either it was James or none of us did it. (L)" -> 2x L is against 1T 1L

Assume James ate it:

James says: "I didn't eat it either (L). Tyler did it. (L)", again, 2xL means James did not eat it.

Assume Dave ate it:

Dave says: "Neither did I (L). James is lying when he said that Tyler ate it. (T)", here we have 1T 1L which is what we are looking for

Finally, assume Tyler ate it:

Tyler says: "I only eat meat (L). If Steve didn't do it, James did it. (L)" Here we have again 2xL so Tyler couldn't have done it either.

Dave's statements are the only ones that fit the 1T 1L requirement. Dave ate it.

 

[kerbiloid]

1. The complainant claims that there was a plate of cabbage soup until he got out from the room. Was it?
As nobody has asked: "What soup? We hadn't seen any soup!", we can take this as a fact. The soup really was.

2. Also, as nobody says: "Why do you think it's eaten, when it is still here, in your plate?", we can agree that the soup really has disappeared.

3. Also nobody says: "You were in the room all the time." or "You ate it yourself, didn't you?", we can take that the complainant indeed had left the room, and the soup has disappeared while he was absent. 

4. Also as nobody claims that a cat ate the soup, or space invaders stole it, we can omit the version of a third person. We can take that indeed somebody of S, J, D, T did this.

5. The compainant's version has at least three logical oddities.
- Why does he claim that somebody ate the soup? He can just claim the soup absence, why is he sure that it's eaten? OK, we can suppose that he tells this being psychologically affected. But this also means that other his claims could be affected as well.
- Why is he sure that only one person ate his soup? Does he want to make us think that there is one exact guilty person? Is he trying to cover up for his own accomplices? Or somebody of this four has already told him the truth?
- Why this strange certainty that one statement is wrong, while another is right? If he doesn't know exactly who did this, how can he be so sure? Does he have an informant between these four persons? Or is he trying to manipulate us?

If he has an informer, why doesn't he tell us? This would exclude one person of four making our task much simpler, as we could presume that the informer tells the truth.
But if the informer tells the truth, then the assumption of "One true, one wrong" is false.
So, either he knows nothing whether somebody tells truth or false, but is trying to make us think that he does. (But why? Does he want to accuse his foe or to make us play his script?)
Or he has an informer who lies us, he.knows that the informer lies and doesn't tell us about this and even keeps from us the fact that he has his own associate between the figures?
In any case he is exactly gambling with us and tries to get his own profit manipulating us.

Ok, let's take a look at other slurry freaks.

6. Steve says: "I didn't eat it. Either it was James or none of us did it."
We can presume that Steve hates James, otherwise why would he make public such claim? How can he proclaim that nobody else can do that?

7. James says: "I didn't eat it either. Tyler did it."
Either James is an honest person and Tyler is the stealer, or James just hates Tyler.

8  Dave says: "Neither did I. James is lying when he said that Tyler ate it."
Tyler is probably a friend for Dave, Dave hates James, Dave and Steve are not friends.

9. Tyler says: "I only eat meat. If Steve didn't do it, James did it."
A slurry person.
Ok, let's believe that Tyler eats only meat. But if we google for a recipe "cabbage soup meat", we get numerous links to a cabbage soup with meat.
So, either Tyler tells the truth, or he ate the meat from the soup, while somebody else ate the soup itself.
Also we can see that he accused everybody but Dave. We can be sure that Dave and Tyler are associates.

10. So.
Tyler and Dave are companions.
Tyler and Steve hate James.
James hates Tyler in turn.
Dave hates James but is afraid to accuse him directly.
Steve is loyal to Tyle and Dave or is afraid of them. (Though he hates James).

11. We can flush down toilet all original bull sheet about "one true, one false" and so on, as we are clearly sure that the complainant tries to make us fools.

 

So, the picture looks like this.
The complainant left his soup in the room and got out.
Tyler (a bully and a musclehead) suggested his minion Dave to eat the soup. Of course, Dave had no objections, but was afraid. Both accomplices agreed to accuse James if somebody asks.
Tyler ate all meat from the soup, while Dave ate the stock with vegetables.
To make Steve be silent, they threatened him (mostly Tyler, of course) and told him to accuse James if somebody asks.
James is a single minded person, nobody of them likes him and nobody even tried to make him keep silence or lie.

So, when the complainant returned to the room and asked "Where is my soup?", James honestly told him what happened. James tells the same to us.

But the complainant doesn't even try to defend James.
Instead of this he includes him in the list of suspected and tries to wash our brains with charades and rebuses as if we are his puppets.

Could such disgusting person be a friend of straight and honest guy James? Never.
So, James' words are sure the most faithful. 

Why James didn't mention Dave among the soup eaters?
Just because James saw sniffing and champing Tyler, fishing out the meat from the soup with hairy and greasy fingers and didn't look how the show would go on.
He is just sure that Tyler did this. (While in fact Dave ate the rest of the soup, too).

 

But how could the complainant leave his soup with such two disgusting persons like Tyler and Dave?
Is he a naive fool? No. Just look at all wise-looking nonsence which he was pouring into our ears.
Also, we know that he is a sneaky person. We can be sure that he left the soup by intention, being sure that Tyler and Dave will eat it.
This was a soup-bait for this pair. Pay attention how acuurately he thought out his sentences to bring you to the assurance that Dave is that bad guy.
Probably, the complainant is afraid of Tyler, too.

So, the picture looks like:
The complainant hates Tyler and decided to weaken him removing his minion Dave.
To do this he thought out a complicated charade-looking version and intentionally left the soup.
When Tyler and Dave ate it, he called for help and brought the facts in a desired form.
He was sure that dullish Tyler without Dave would become more vulnerable, while cowardly Dave will betray his friend being directly accused.

So, Tyler and Dave ate the soup provocated by the complainant.

Edited December 19, 2016 by kerbiloid

[Shpaget]

I'll have to go with the @5thHorseman and his reasoning.

Also, I must agree with @LordFerret.

 

@LN400, while your method brings us to the same conclusion, is that a valid approach to solving this type of riddles? It seems like a fluke it worked here.

[LN400]

8 hours ago, Shpaget said:

@LN400, while your method brings us to the same conclusion, is that a valid approach to solving this type of riddles? It seems like a fluke it worked here.

By assuming, you can show that the assumption leads to absurdities (such as both statements are true or both statements are false when the riddle states that one statement must be true while the other must be false).

[Candlelight]

On 19.12.2016. at 8:25 AM, Shpaget said:

I'll have to go with the @5thHorseman and his reasoning.

Also, I must agree with @LordFerret.

 

@LN400, while your method brings us to the same conclusion, is that a valid approach to solving this type of riddles? It seems like a fluke it worked here.

Took a bit of time myself, and i do have to agree, @5thHorseman and @LN400 were right...

@LordFerret that's the first thing that came to my mind when first seeing the question...I wouldn't really get that mad over soup to the point that i have to interrogate people, that's just not me lol...

I think @stibbons short summary is also cool...

But my biggest props goes to @kerbiloid.Your detective-like, extensive analysis really amazes me, you sir either have a great mind or i'm just asleep half the time...

Edited December 20, 2016 by Candlelight

[Randox]

Might enjoy False Logic Puzzles by Norman Willis. The whole book is puzzles that work like this, though most of them are harder such that you can't instantly rule out each incorrect suspect by their own statements. It takes a while to get used to solving this kind of logic puzzle, but once you get into it, they're a lot of fun.

 

My reasoning would be the same as LN400, though I like how Stibbons got it.

[Diazo]

Interesting question. Posting my answer before reading the rest of the thread.

Spoiler

As there are only 4 suspects, I brute forced it:

1) It was Steve!

Steve says: "I didn't eat it. Either it was James or none of us did it." --> If it was Steve, his first statement is false, so the second statement must be true! But that means James did it?

Contradiction so it can't be Steve.

2) It was James!

Steve says: "I didn't eat it. Either it was James or none of us did it." --> First statement true, second statement false, could still be be James as the "none of us did it" is still false, making the entire second statement false.

James says: "I didn't eat it either. Tyler did it." --> James did it so first statement true, second is false. Could still be James.....

Dave says: "Neither did I. James is lying when he said that Tyler ate it." --> Dave didn't eat it, but it is also true that James is lying about Tyler,

Dave told two truths so it's not James.

3) It was Dave!

Steve says: "I didn't eat it. Either it was James or none of us did it." --> First statement true, second statement is false because James didn't do it.

James says: "I didn't eat it either. Tyler did it." --> Dave did it so first statement true, second is false. Could still be Dave...

Dave says: "Neither did I. James is lying when he said that Tyler ate it." --> Dave ate it so first statement is false and second statement is true as James's statement that Tyler did it is a lie. (and also false).

Tyler says: "I only eat meat. If Steve didn't do it, James did it." --> The first statement is meaningless, even if it's false and Tyler does eat cabbage, that doesn't mean he ate this bowl of soup. Second statement is false, so Tyler eating only meat is true.

Could be Dave.....

4) It was Tyler!

Steve says: "I didn't eat it. Either it was James or none of us did it." --> First statement true, second statement is false because James didn't do it.

James says: "I didn't eat it either. Tyler did it." --> Tyler did it so first statement false, second is true.

James told two truths, can't be Tyler.

IT WAS DAVE!

The interesting part about this is what is false? Take the "Either it was James or none of us did it." If this statement is False, does that mean BOTH James didn't do it and that one of us did it?

In solving the puzzle, I took it to mean that both parts of the statement had to be true for it to be true, otherwise it was false. But if you take that statement to be false only if both conditions are false, it changes the reasoning for why it couldn't be James who ate the soup even if it doesn't change the conclusion that it was Dave who did it.

D.

edit: After reading the thread, it is interesting to see that while I did reach the same conclusion I did it differently in that I went in order every time, while the rest of the thread started with the person making the statement first instead of from the top each time.

Edited December 21, 2016 by Diazo

[Superfluous J]

6 minutes ago, Diazo said:

The interesting part about this is what is false? Take the "Either it was James or none of us did it." If this statement is False, does that mean BOTH James didn't do it and that one of us did it?

When you have an "or" in logic then the statement is true if either thing you're "or"ing is true. Adding the "either" implies that only one of the two can be true, but I'm not sure if that's actually a logical constraint. But let's assume it is because hey language and stuff. It's what I assumed above.

So, if James did it it's true, and if none of them did it it's true. If James did it AND none of them did it it'd be false, and if James didn't do it but someone else did it's also false.

[James Kerman]

They all ate it according to the many worlds theory.