The International System of Units (SI) [72 page pdf Brochure] is maintained by the Bureau International des Poids et Measures at it’s headquarters in Sevres near Paris, France. The Metric System as it is often known has a long history; supposedly invented in 1670 by Gabriel Mouton, a French clergyman, It was adopted by France in 1795 and by the United States in 1866. The system gained international status with the signing of The Convention of the Meter in Paris on 20th May 1875. The U.S. was one of the original seventeen signatory nations and is the only industrialized nation that still does not use the system.
Note: At this time, only three countries – Burma, Liberia, and the US – have not adopted the International System of Units (SI, or metric system) as their official system of weights and measures. Although use of the metric system has been sanctioned by law in the US since 1866, it has been slow in displacing the American adaptation of the British Imperial System known as the U.S. Customary System. The US is the only industrialized nation that does not mainly use the metric system in its commercial and standards activities, but there is increasing acceptance in science, medicine, government, and many sectors of industry.
CIA World Fact Book. 2000
In 1971 the U.S. Metric Study by the National Bureau of Standards resulted in a Report to the Congress called “A Metric America, A Decision Whose Time Has Come.” The report recommended that the U.S. should switch to the metric system deliberately and carefully through a coordinated national program, and establish a target date 10 years ahead. In 1992 NIST the National Institute of Sciences (The Successor to the National Bureau of Standards) published a report titled A Metric America: A Decision Whose Time Has Come – For Real (NISTIR 4858) June 1992. The US has spent over a century trying to switch to the metric system through a process of voluntary adoption.
The SI is without question more rational that the US Customary System and the British Imperial System on which the US system was based. But it has failed to gain acceptance in the US and its adoption in many other countries has been painfully slow. This is a classic example of the influence of network effects resulting in lock-in. But it is also an example of economic protectionism masquerading as defence of cultural heritage and patriotism. The adoption problems of the SI are not unique. When an established ontology is challenged by a newer ontology there will be resistance to the new ontology no matter how good it is. Ontologies are like Khunian Paradigms; new ontologies are resisted by those who have a vested interest in the old system. Ontologies, like jargon, can form barriers to market entry that effectively exclude potential competitors and protect established players. The benefits provided by these barriers can outweigh the benefits of adopting the new ontology. In such cases voluntary adoption will not occur. Establised players are acting out of self interest in resisting change.
Effective conversion from an old established ontology to a new replacement ontology requires more than encouragement it must be accompanied by coercion. In the UK enforcement of the metric system is proceeding through government mandated use in; the education system, the military, all government contracts and for all commerce. Government departments are also aggressively pursuing offenders like Tesco through the courts. This policy has generated a backlash. Groups like the BWMA are mounting popular resistance campaigns aimed at preventing change.
Building a great ontology is only the first step. Getting people to adopt it is far more challenging. Adoption is not driven by the merits of the new ontology alone. Enforcement is often required. The US will not become metric until congress is prepared to enact enforceable laws that mandate the use of the metric system.