Maybe Galton's classic twins study was invalid: perhaps you cannot look at the similarities between identical twins, and those between non-identical ones, and conclude that the difference must necessarily be due to genes.

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First, it's important to note that the pair of myTouch devices are identical in componentry and general design, with the major difference being that the myTouch Q is a bit thicker due to its slideout keyboard.

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In other words, the price difference between a chocolate bar in England and an identical bar in the United States may not be completely arbitraged away by the importation of U.S. chocolate bars because there is still the matter of transportation costs.

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Note that the real return since 1926 is almost 1% per year higher, a fairly material difference in terms of returns, and yet the nominal return was almost identical (9.9% annually since 1926 versus only a slightly lower 9.7% since 1957).

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And how can we so clearly tell the difference between chemicals that on a molecular level are nearly identical?

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