Only the fool would take the trouble to verify that his sentence was composed of ten a's, three b's, four c's, four d's, forty-six e's, sxteen f's, four g's, thirteen h's, fifteen i's, two k's, nine l's, four m's, twenty-five n's, twenty-four o's, five p's, sixteen r's, forty-one s's, thirty-seven t's, ten u's, eight v's, eight w's, four x's, eleven y's, twenty-seven commas, twenty-three apostrophes, seven hyphens, and, last but not least, a single !
Ladies and Gentlemen, I am that fool. It's a perfectly true sentence, but it'd be a lot of work to translate it into other languages.
To be fair, it's not original. It's a literal textbook example used for pedagogic purposes in one of my grad-school textbooks on Search. Yes, "Search" is an entire field of study.
If anyone cares, the sentence above represents one solution of a system of nonlinear discrete equations. Such systems are generally considered insoluble, UNLESS (A) there are many solutions in the search space and (B) the value of each term has consistency constraints against less than half the other terms, and (C) the number of possible values each variable can take is expected to be less than n*log(n) of the number of variables. If these things are true, then a system of nonlinear discrete equations can be solved (or at least one of the solutions can be found) using an obscure algorithm called Cycle Search.
Cycle Search is not usually implemented even in databases or advanced mathematical packages, because people don't understand the constraints on its usability and when they try to use it on problems that don't meet the constraints it diverges hard. Besides, solving such systems is considered bizarre and likely to be useless for any practical purpose. They are far more likely to implement a loosely-related algorithm called the RETE algorithm. RETE is usable on a set of problems considered far more practical and valuable, and doesn't require the variable values to be numeric. It could in theory be used on problems like the above, but the RETE algorithm diverges hard on nonlinear cases and would take until well after the sun burns out to find a solution to this.
A sentence like the above is a "small" instance of such searches. If you are sufficiently OCD, you can do it on paper, by hand (translate that sentence into another language) in about a week with less than 500 pages of paper to work on. Which is about the same amount of time it takes a good programmer to correctly implement Cycle Search, so it's pretty much a break-even case. If a problem the same size as the above had only one solution, it could, in theory, eventually be found using Cycle Search, but it might take several centuries of computer time. Not as bad as RETE, but in a one-solution case, pretty bad.
