Re:Huh? (Score 1)

It also matters from a philosophy-of-science perspective *to the metric system.* While in practical terms it's the usefulness of the metric system which stands as its ultimate justification, it also helps keep the metric system on the same page as good scientific practice if its basic postulates are somehow empirically verifiable. Imagine what it would be like if the metric system was based on the idea of the length of the staff of God, or on the number of angels who can dance on the head of a pin. It doesn't fit right with the rest of the scientific project -- it's like putting peanut butter in your spaghetti sauce. If the metric system *was* set up this way, one can imagine it feeling competitive pressure from a similarly efficient and congenial system of measure based on the empirically verifiable properties of middle-sized objects; e.g., spheres of silicon. Now, you might not think that much is gained by going from a chunk of platinum to a sphere of silicon, but science is all about incremental improvements, and (as the article and other posters point out) there are certain properties of a silicon sphere which make it a more reliable/stable proxy for the ideal kilogram. (Remember, the closer your empirically verifiable properties are to the ideal properties you postulate, the better your scientific theory.)