Pournelle's chart is more theoretical: its axes are statism and
belief in the possibility of accurate social engineering. (Which
are not the same thing!)
The Nolan Chart is more pragmatic: its axes are "Personal Freedom"
(sex, drugs, the draft) and "Economic Freedom" (minimum wage, taxes,
licensing). Used with the "World's Shortest Political Quiz", which
some have criticized for its quick'n'dirty selection of questions
which may tend to overestimate the number of libertarians.
(Dave Nolan is a founder of the LP.)
I once met someone who objected to the Nolan Chart because it's square
and a hexagon is a more natural shape!
Anton Sherwood *\\* +1 415 267 0685 *\\* DASher@netcom.com