Left and right began as seats in a French revolutionary assembly
During the French Revolution, the aristocracy sat to the right of the speaker, the traditional place of honour, and commoners sat to the left. Right came to mean support for the old order of crown, nobility and church; left meant republicanism, secularism and civil liberties. A seating chart became the world's most durable political map.
Many political scientists consider a single left-right line too crude, and popular two-axis charts usually add a social dimension running from authority to liberty alongside the economic one. Liberalism shows the problem neatly, landing on the left in some countries and on the right in others. Researchers have tried for nearly a century to find the real dimensions of political opinion using statistics.
In 1950 Leonard Ferguson measured American attitudes on ten subjects, including birth control, capital punishment, censorship, evolution and war. Factor analysis yielded three clusters he named religionism, humanitarianism and nationalism. Religionism and humanitarianism replicated well; nationalism did not. Soon afterwards Hans Eysenck, who had left Nazi Germany for Britain, surveyed British opinion using statements drawn from newspapers and pamphlets. He found a familiar radical-conservative factor and a second one he called tough-minded versus tender-minded, and he believed it revealed what Nazis and communists had in common: both scored as tough-minded.
The two studies turned out to agree. Rotating Eysenck's pair of axes by 45 degrees produces Ferguson's religionism and humanitarianism, and Eysenck's dimensions also emerged from surveys in Germany, Sweden, France and Japan. In his 1956 book Sense and Nonsense in Psychology he reported that left and right captured most variation in Britain and the United States, while the tough-tender axis loomed larger in France.
Critics pounced. Factor analysis will always produce a factor whether or not anything real lies behind it, almost no values loaded purely on the tough-tender dimension, and Eysenck's attempt to link toughness to extroversion and psychoticism gave ambiguous results. Milton Rokeach challenged his Nazi-communist finding on technical grounds and in 1973 proposed his own two axes, freedom and equality, arguing that the left's defining trait is valuing equality more than the right does.
Source: Political spectrum
