"Nec eventus modo hoc docet, stultorum iste magister est, sed eadem ratio, quae fuit futuraque, donec res eaedem manebunt, immutabilis est."
Livy, History of Rome, Book 22
And it is not only the result that will instruct them, that teacher of fools, but reason itself, which was and will be unchanging, so long as the same fundamental conditions still hold.
“Some economists, when thinking about long memory, are concerned that it undercuts the Efficient Market Hypothesis that prices fully reflect all relevant information; that the random walk is the best metaphor to describe such markets; and that you cannot beat such an unpredictable market. Well, the Efficient Market Hypothesis is no more than that, a hypothesis. Many a grand theory has died under the onslaught of real data.” Benoît B. Mandelbrot