"A study performed between 1907 and 1919 in 140,000 healthy adults applying for life insurance in the New York region suggested that a blood pressure of 140 (systolic)/90 (diastolic) mm Hg was abnormal because it reflected only 5-6% of the population in the United States (9); however, by nature, these early studies may not have been representative of the general population because they usually did not include subjects of lower socioeconomic status who could not afford insurance or patients who had been previously diagnosed with a disease. Nevertheless, on the basis of these early studies, a blood pressure of 140/90 mm Hg was adopted as the definition of hypertension."

I think that I'm seeing a pattern. How do we create a standard or definition of something? Often we have only that which is readily available or our experiences in order to understand things. In addition to the above example of creating a definition of "normality" in blood pressure, Milk has been used as the standard for substances containing calcium. For a long time nothing else was known to contain more calcium. Milk thus became the standard. It was a 10 and any other substance was given a ranking on this scale. I think this practice often applies to more abstract things like thinking patterns, conception of beauty, and cultural morals and norms. The French Academy of Arts for over a century had a very narrow definition of what was a beautiful painting. Those paintings which did not match this definition were rejected as was the case with the impressionist painters. The impressionists are now the recognized as beautiful while the old standard is almost forgotten.