We must, however, remember that while correlation does not imply causation, causation does imply correlation. Where there is a causal link, we should find a correlation. If you find no correlation between age and shoe size among adults, then you can safely conclude that after the end of adolescence, age does not make feet grow larger and that you have to look elsewhere for the causes of differences in shoe size. In short, wherever there is causality, there is correlation. It follows that where there is causality, we should be able to predict—and correlation, the accuracy of this prediction, is
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