Logically Speaking, You Should Take This Quiz

Answer: True

Think about it like this. If all squares are rectangles, and all rectangles are quadrilaterals, then all squares are definitely quadrilaterals. Think about it as going from specific to general.

Answer: False

Try this one: If all squares are shapes, and some shapes are circles, then some squares are definitely circles. No! Thus, it's false.

Answer: False

This situation is brought up every now and then, like in "The Princess Bride", when Westley challenges Vizzini to this game of wits. There is no way to reason your way to figuring out which glass the poison is in, because every bit of logic you come up with, your opponent could have already foreseen, and gone one step further.

The only way to play this game is to pick one randomly and hope for the best.

Answer: 99

The best plan you can come up with will actually be guaranteed to save 99/100 men, with the remaining person having a 50/50 of survival. Here's how it works: The night before, you decide that the 100th person (the guy in the back who goes first) will count the number of white hats in front of him, and say "white" if there are an even number of white hats and "black" if there are an odd number of white hats. (He is the guy with a 50-50 chance.) The 99th guy counts the number of white hats in front of him, and based on what the 100th guy said, says whether he has a white or black hat. The 98th guy counts the number of white hats in front of him, and based on what the 99th and 100th guys said, decides whether his hat is white or black. And so on down the line.

I've had a lot of people send me notes saying that you should just say the color of the hat the person in front of you is wearing. If you did that, it might help out the person in front of you, but it does nothing for you. If the person in front of you had on a white hat and you were wearing a black hat, you'd get shot for saying "white".

Answer: Yes

The best way to explain this is to consider 3 scenarios:

A: You see 2 black hats. You immediately know you have a white hat on because there are no more black hats left.

B: You see 1 black hat and 1 white hat. You know you can't have a black hat (i.e. you have a white hat) because then the person with the white hat would have scenario A, and would have answered immediately.

C: You see 2 white hats (the scenario in the question). You can't have a black hat (i.e. you have a white hat) because then both of the other people would have scenario B, and would have already answered 'white'.

Thanks to HansElcid for this explanation which was much clearer than the one I originally had.

Answer: False

This is the question you should ask (to either guard): "If I were to ask the other guard which door leads to fame, fortune, and happiness, what would he say?"

Lets say that door A leads to painful death and door B leads to fame, fortune, and happiness.

The truthful guard would say, "He would tell you to go through door A." He would be telling the truth that the other guard (the liar) would tell you to go through the wrong door.

The fibbing guard would say, "He would tell you to go through door A." He would be lying by telling you that the truthful guard would tell you to go through the wrong door.

Basically, ask the aforementioned question, and don't go through the door the guard tells you.

Answer: green

If it's a blue elf (always tells the truth), then the statement "I always lie" is false, thus creating a contradiction because the elf who can only speak the truth just uttered a false statement.

Likewise with the red elf (always lies). If he speaks this statement, it would be true, thus creating a contradiction because the elf who can only lie just uttered a true statement.

If the green elf says it though, the statement is a lie, but unlike the other elves, the green elf is not bound to any one type of statement, so no paradox is created.

Thus, you must be talking to a green elf.

Answer: True

I got this idea of a crazy sentence from xaosdog so I tried to make one of my own.

This statement is saying: There is a woman who likes a man who happens to be at a bar that is closing. Even though the bar is closing, the man bothers Cat, who is from Moose, WY, to let him spend the night at the bar.

More formal explanation for the first part of the sentence:
1. "the woman likes" is an adjective phrase describing "the man"
2. "the man the woman likes" is the subject for the predicate "is at"
3. "the man the woman likes is at" is an adjective phrase describing "the bar"
4. "the bar at which the man the woman likes is" is the subject for the verb "is closing"
5. Putting it all together leaves you with "...the bar at which the man the woman likes is is closing..."

The sentence is certainly awkward, but it is correct.

Hopefully that clears up any questions.

Answer: Jack and Jim are the only possible duo that could have robbed the store.

The condition that one of the guilty ones was telling the truth is key. The only persons who could possibly be guilty AND tell the truth are Jack or Jared. If Jared is the guilty one telling the truth, then the only possible pair is Jack and Jared. However, this means that Jack is also telling the truth, thus it is not an option.

This means that Jack has to be the guilty one telling the truth. This means than neither John nor Justin could be guilty, or else Jack's statement would be false. We've already ruled out Jack and Jared as partners, so the only two possible pairs left are Jack and Jim, and Jack and Joe. Now we look at John's testimony. We know he's lying (because we know Jack is guilty) which means that Joe could not have done the robbery, leaving Jack and Jim as the only possible pair left.

Answer: Yes

Hopefully, if you know English, you should quickly be able to recognize three errors. "Their" should be "there", "erors" should be "errors", and "sentance" should be "sentence". However, this is only three errors, so the fact that it says there are four errors is in itself an error. However, as soon as you recognize this as an error, there really ARE four errors in that sentence and "four" isn't an error anymore. However, as soon as you accept the fact that "four" isn't an error anymore, then there are only three errors and now "four" is an error again. And so on. This makes it a paradox.

A good correction would be: "There are no errors in this sentence."