The chart further illustrates the claim that Libertarianism is diametrically opposed to authoritarian control systems such as communism and fascism. David Nolan of the United States Libertarian Party created it in 1970, redefining labeling of ideology in terms of government involvement. He used it to explain how libertarianism differed from the Republican and Democratic partisan platforms.
Differing from the traditional left/right distinction and other political taxonomies, the Nolan Chart in its original form has two dimensions, with a horizontal x-axis labeled "economic freedom" and a vertical y-axis labeled "personal freedom". It resembles a square divided into four quadrants. The upper left quadrant represents liberalism — favoring government that taxes more and spends more for activities such as welfare, Social Security and funding for the arts and that encourages more barriers on trade and business regulations (which David Nolan labeled "low economic freedom"), but supporting personal choice in issues such as marijuana, homosexuality and the draft (which he labeled "high personal freedom"). At the bottom right is its converse, conservatism, whose coordinates place it as supporting high economic freedom and low personal freedom. Conservatives want lower taxes and fewer social programs but support regulation by the government of cultural issues and personal behavior. The Nolan Chart places David Nolan's own ideology, libertarianism, at the top right, corresponding with high freedom in both economic and social matters. The fourth quadrant at the bottom left represents the antithesis of libertarianism. David Nolan originally called this philosophy populism, but many later renditions of the chart have used the label authoritarianism instead.
The Nolan Chart has also been rotated and visually represented in a few other ways, such as having conservatism and populism/authoritarianism at the top and libertarianism and liberalism at the bottom. In another popular portrayal, the Nolan Chart takes a rhomboid form, with left representing liberalism, right representing conservatism, down representing authoritarianism, and up representing libertarianism.
The chart is inspiration for many political self-quizzes based on these four categories—liberal, libertarian, conservative and populist/authoritarian—of political thought, many of which have been written in computer code to be taken by visitors on the Internet. The site FreedomKeys.com provides links to a variety of charts using the same essential ideas using different names or survey questions.
The advocates and writers of these quizzes are most often libertarian, and a common remark by them about their tests is that people who are libertarians inside and didn't know it will discover their true political leanings. The detractors of the Nolan Chart are most often people who accuse people with libertarian beliefs of using it to further their agenda and gain converts to their party and political movement. One specific accusation is that libertarian "recruiters" try to convince people that, because they hold several libertarian positions, they should consider making all their positions libertarian in order to achieve consistency in advocating liberty.
Critics of this diagram, (and this kind of chart in general) claim that it represents at best a pseudoscientific illustration of a political point of view. The essential premise of the diagram is for many an oversimplified generalization; economic freedom and personal freedom are often inextricable, and both left-wing (Bakunin) and right-wing philosophers draw the same connection. Critics insist that the Libertarian claim (and associated chart) rests on either the utilitarian assumption that Libertarianism is a workable alternative to older, more familiar political systems or on the moral argument that it would be better if only because it would leave people freer. This freedom, in the extreme, may be perceived by some as tending toward anarchy, and driven by excessively self-centered or selfish motivation. In essence, they claim the "chart" exists only to distance the term "Libertarianism" from the older terms of anarchism and socialism, the latter of which draws polemic connections to communism, which itself draws polemic connections to tyrannical fascism and totalitarianism.
Proponents, on the other hand, point out that if anything is pseudoscientific, oversimplified and demonstrably misleading, it is the ancient "left-right" political spectrum which has been around for centuries and is still in use almost everywhere today. The problem with that old linear spectrum, they say, is that it is used so often to put one type of authoritarianism, communism, on the left, and another type of authoritarianism, fascism, on the right, and imply that freedom is in the middle, as though it were some kind of compromise between, or combination of, the two allegedly "opposite" totalitarian extremes. This, they say, is absurd on its face and essentially leaves freedom and limited-government advocacy actually out of the picture and out of consideration. Thus the "left-right" spectrum is deeply flawed, woefully inadequate, and thereby useless, except to authoritarians and advocates of government-enforced altruism who advance their agendas by sowing confusion. So the Nolan chart was developed primarily to fix these problems.
A few of the people who oppose the use of the Nolan Chart are strong libertarians, objectivists or other individualists who believe that the political spectrum need be portrayed only through one dimension -- totalitarianism/authoritarianism (statism) vs. liberty, i.e. those who support government control of people's lives vs. those who support freedom. They consider in what arenas such control exactly is exercised to be irrelevant.
One variant on the Nolan chart is the Vosem chart, which adds an additional axis to represent personal positions on corporate issues.