# Articles

Gödel and the limits of logicWhen Kurt Gödel published his

*incompleteness theorem*in 1931, the mathematical community was stunned: using maths he had proved that there are limits to what maths can prove. This put an end to the hope that all of maths could one day be unified in one elegant theory and had very real implications for computer science.**John W Dawson**describes Gödel's brilliant work and troubled life.
The right spin: how to fly a broken space craftOn the 25th of May 1997 a dramatic collision tore a hole into the space station

*Mir*and sent it hurtling through space. As NASA astronaut**Michael Foale**tells*Plus*, the fate of*Mir*and its crew hinged on a classical set of equations.
Graphical Methods II: The return of the slimeIn last issue's Graphical methods I

**Phil Wilson**used maths to predict the outcome of a cold war in slug world. In this self-contained article he looks at slug world after the disaster: with only a few survivors and all infra-structure destroyed, which species will take root and how will they develop? Graphs can tell it all.Editorial

- Plus new writers award - Maths is the language of the universe, so what have you got to say?
- Reader's corner - 6174 and other mysterious numbers.
- World Cup maths - How Plus can help you with your football.

Symmetry rulesEveryone knows what symmetry is, and the ability to spot it seems to be hard-wired into our brains.

**Mario Livio**explains how not only shapes, but also laws of nature can be symmetrical, and how this aids our understanding of the universe.
Mysterious number 61746174 is a very mysterious number.

**Yutaka Nishiyama**explains why, and how beautiful mathematical oddities can inspire us to discover new mathematics.
Graphical methods I: Slug warsTo arm or to disarm? This is the question in

**Phil Wilson's**article, which explores the maths behind a cold war in slug world.
Anything but square: from magic squares to SudokuGet on a commuter train these days and you can virtually see people's brains crunching away at filling the numbers from 1 to 9 into a square grid. As the Sudoku craze shows no sign of slowing,

**Hardeep Aiden**investigates its relatives and predecessors.