The Number of Letters (Leta I)

One of my absolute favorite puzzles from when I was a child – and honestly, maybe the puzzle that got me into puzzles in the first place – was this simple phrase in a book that I’ve forgotten the name of.

 

“The answer is the number of letters in the answer.”

 

 I’ll give you a chance to solve it before I discuss it more – it’s really elegant and worth a thought, I think.

 

 ~ ~ ~ ~ ~

 

The given answer is four. Four is the only word, in English, that has the same number of letters as its value. That’s a very interesting and universal fact that this puzzle is built around, and thinking about it and solving it leads you naturally to that fact! That’s what sets this puzzle apart from many other, more contrived puzzles.

But there is another answer that was suggested by the book: 0. Because 0 is a numeral and not a letter, it also contains the same number of letters as its value. Which brings me to an interesting question… what else has this quality? Surely lots of different phrases and mathematical expressions work, and there’s a tapestry of answers instead of just “four” and “0”!

All that’s left is to give this problem a terrible name, just like the rest of em. It’s about a number or expression having a self-referential or meta number of letters… meta letters – Leta. That’s appropriately bad, I think. If an expression has a number of letters equal to its value, call it Leta. So, next time, let’s try to investigate what kinds of expressions are Leta!