Print This Page

An Amusing New Paradox

An Amusing New Paradox
Don Knuth (Stanford University)
  • 03 Nov 2015 - 03 Nov 2015
  • 10am- 12noon
  • BHSC G.06

Lecture with Don Knuth

Donald E. Knuth is an American computer scientist, mathematician and professor emeritus at Stanford University, author of the multi-volume standard work The Art of Computer Programming, father of the Analysis of Algorithms, and creator of the TEX computer typesetting system. Don received the ‘ACM Grace Murray Hopper Award’, the ‘ Turing Award’, the ‘National Medal of Science’, the ‘John von Neumann Medal’, and the ‘Kyoto Prize’.

He is visiting UCC, the week beginning 2 November, to receive an honorary doctorate degree which recognises his enormous contribution to the field of Computer Science and has kindly offered to present a lecture to our staff and students - an opportunity not to be missed.

What could be more amusing than trying to write a program to solve a fiendishly difficult puzzle?

Don Woods, who is well known as the co-author of Adventure (the cave-exploration game that went viral in the 1970s) as well as INTERCAL (the worst-ever programming language), came up with another  insanely great and delightfully preposterous creation in 2000 - an innocuous little broadside entitled 'Twenty Questions'.

Twenty Questions is a multiple-choice exam, which starts out as follows:

1. The first question whose answer is A is (A) 1  (B) 2  (C) 3  (D) 4  (E) 5.

And the other nineteen questions get progressively worse and worse, leading to a grand climax.

The original version of this questionnaire had problems, and it was 'cooked' by several people. In fact, the task of finding the best possible list of answers has turned out to be an exceedingly difficult challenge to computer programmers, who haven't been able to avoid bugs in their code. In fact, every one of the many contributors whose work has been published so far has made serious errors.

With a small change to Woods's original specification, the questions can now be optimally answered for the first time.

But with two more tiny changes, a mystery arises, which challenges everything the speaker thought he knew about logic.

He will give an explanation that, thank goodness, resolves the paradox  - or does it?

Places are limited, so please confirm your attendance on An Amusing New Paradox, lecture by Don Knuth.  

This lecture is dedicated to George Boole and Ada Lovelace, on the occasion of their 200th birthdays, as well as to Lewis Carroll, on the 150th anniversary of Alice's Adventures. 

« Previous Item

Next Item »

« Back to Lecture Series