When you categorize people?s political views as either conservative or liberal, you might ignore important distinctions ? the types of distinction brought out more effectively in the ?Nolan Chart? that appears below.

(For instance, the chart helps astute observers recognize that the terms ?conservative,? ?libertarian,? and ?Republican? are not synonymous.)

The latest TIME offers a short obituary of the chart?s namesake, 66-year-old David Nolan, a co-founder of the Libertarian Party.