You need to define "intelligence" before you can determine a way to measure it. Despite many attempts, all intelligence tests include some forms of social, economic, political, cultural, racial or other biases and prejudices.. A few examples:
1) Culture: Could you solve a simple math question if it were worded in Mandarin Chinese, the most spoken language in the world? No? Are a
billion Asians (mostly Chinese in this case) more intelligent than you?
2) Socio-economic: Could Mozart have solved a math problem (worded in German or Italian - he spoke both languages)? If not, was Mozart lacking intelligence?
3) Blatant discrimination: U.S. literacy tests for voting, finally abolished by the Voting Right Acts of 1965. If you were African-American when these "tests" were in effect and could not read, for example the U.S. Constitution, you could not vote. If the voting authorities knew you were a literate African-American, you might have gotten the same test but in German. Were southern Blacks in 1950 stupid?
4) Eugenics: "... Three generations of imbeciles are enough." Justice Oliver Wendel Holmes Jr. delivering "the U.S. Supreme Court's decision upholding the Virginia sterilization law in Buck v. Bell", 1927. Though eugenics is not uniquely limited to the U.S. or the 20th century, many U.S. states enforced mandatory sterilization laws in the 20th century. From
wikipedia: "In the end, over 65,000 individuals were sterilized in 33 states under state compulsory sterilization programs in the United States." Finally abolished in 1983. Is the U.S. any smarter today because of earlier forced sterilization?
5) Cultural: The term "Caucasian", now commonly used to describe "white" people, was coined circa 1800 by Johann Friedrich Blumenbach in creating a hierarchy of races. Caucasian was the archetype of humanity; other races were lower. From
wikipedia: "Caucasian variety - I have taken the name of this variety from Mount Caucasus, both because its neighborhood, and especially its southern slope, produces the most beautiful race of men, I mean the Georgian; and because all physiological reasons converge to this, that in that region, if anywhere, it seems we ought with the greatest probability to place the autochthones (birth place) of mankind."
6) Military intelligence: Sample questions from a 1917 U.S. Army mental test:
Crisco is a: patent medicine, disinfectant, toothpaste, food product.
The number of a Kaffir's legs is: 2, 4, 5, 8.
Christy Mathewson is famous as a: writer, artist, baseball player, comedian.
Are (were) you smart enough to join the Army?
The last example and other un-cited quotes are from
The Mismeasure of Man by Stephen Jay Gould. The book provides a good historical study of intelligence/innateness and the many flawed attempts to define and measure ("mismeasure") intelligence. The
Revised and Expanded version debunks the popular but biased 1980's book
The Bell Curve and its concept of "
g".