Thursday, April 5, 2007

Fun with Quotes

Back when I was TFing for QR22 I used to pass the time by making up puzzles. At some point, I came up with some quote puzzles (of the standard use/mention type) which I proposed to Peter as extra credit problems. He thought we had best not use them, which in retrospect was a wise decision. Anyway, no reason they should go to waste, so here they are!

To answer these puzzles, all you have to do is put a certain number of quotes into the given sentence to transform it into a truth. To give you a feel for the locutions I use, the following sentence has two quotes in it, the first of which is an opening quote, and the second of which is a closing quote.

“Boston” names Boston

Puzzle (1) below is my attempt to create a slightly more challenging limerick puzzle than the well known one given in most logic classes which features the sentence about Boston above. One of (2) - (4) throws self-reference into the mix. One of the nice things about puzzle (4) is that (so far as I know) it has a unique solution. (6) is inspired by part of Dave Gray's recent Eminees presentation. I might post hints in the comments. Enjoy!

(1) A few quotes placed right help construe
the sense of this jumbled word stew:
James names names names James
names names names James names
names names James names names, which is true.

(2) This sentence has the quoted expression this in it, but there is no instance of it unquoted.

(3) This sentence has exactly two instances of in it.

(4) The number of quotes in the sentence on this page beginning with the words the number of quotes on this page is three, and moreover, they are all opening quotes occurring before the first letter t in it.

(5) This sentence uses but has no mention of the word akimbo.

(6) Names name names name name.

8 comments:

Christopher Furlong said...

Here's my guess for #2. I'm no longer sure it's right, but James assures me it is.



(2) This sentence has 'the quoted expression this' in it, but there is no instance of it unquoted.

Aaron said...

Number (1) goes:

""""James names names"" names "James
names names""" names """James names
names"" names "James names names"", which is true.

Aaron said...

and numero three has at least two solutions:

This sentence has exactly two instances of “”” in it.

This sentence has exactly two instances of ““” in it.

Simon Rippon said...

(5) "This sentence uses but" has no mention of the word "akimbo".

(6) Names name names, ""name"" "name". [Can I put in a comma?]

Simon Rippon said...

An alternative solution for 3?

3) This sentence has "exactly two instances of" in it.

Simon Rippon said...
This comment has been removed by the author.
Simon Rippon said...

(4) The number of "quotes" in the sentence on this page beginning with the words "the number of "quotes"" on this page is three, and moreover, they are all opening quotes occurring before the first letter "t" in it.

Did you have a typo in this, James? Maybe you meant:

(4) The number of "quotes" in the sentence on this page beginning with the words "the number of "quotes" in the sentence on this page" is three, and moreover, they are all opening quotes occurring before the first letter "t" in it.

James said...

Chris' post has a solution for (2) from what I can see, though I had another in mind:

""This" sentence" has the quoted expression ""this"" in it, but there is no instance of "it" unquoted.

Chris' solution might be better since it avoids problems with capitalization.

Aaron has what I took to be solutions to (1) and (3).

Simon has (5), but I'm not sure his (6) works, even with the comma. A hint: (6) should be read the way one reads sentences like "dogs dogs dog dog dogs" or "Buffalo buffalo buffalo buffalo buffalo".

I like Simon's alternate solution to (3). I did make a typo in (4) just like Simon suggests (though it doesn't really affect my anticipated answer). I don't think Simon's solution works (though it is very creative) since the part of the sentence after "moreover" doesn't seem true.