Peter Birkenhead, a Salon writer, speculated about the stupidity of people who bought The Secret (mostly in the context of lambasting Oprah's endorsements of it) and an acquaintance of mine quipped, "Does the author really think that the all the millions of people who have bought The Secret are total morons?" To which I replied:
Well, "moron" used to be the clinical term for people whose IQ fell in the range of 51-70 (e.g., a 20-year-old with the intellectual capacity of a 12-year-old). Given that IQ is a normal distribution (bell curve), and allowing that "total moron" would be a more restrictive category than "moron", therefore mathematically defining it as the third standard deviation below normal, we find that in a world of 6 billion people, there are 16.2 million "total morons."
Since there are only 5.75 million copies of The Secret in print (counting the publisher's 1 March reorder of 2 million copies), it is entirely mathematically possible that "all the millions of people who have bought The Secret are total morons". However, since I know at least a few demonstrated non-morons who've at least read, if not bought, the book, it's clear that, if Birkenhead does believe this, he is wrong.
This episode has been brought to you by the numbers 'n' and 'p', and the letter 'σ'. ;-P