I said that I would leave if asked to by an authority on this site. I haven't been asked to, but I've been informed that all my posts will be deleted from now on. I'll take that as an invitation to leave.
I promise not to return and post under this username or any other. Since I won't be able to respond, please resist posting any more comments with regard to my prediction. Thanks.
Go on, vote this one up. Show you have a sense of humor.
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Sorry, last post ever (unless you want to invite me back).
The answer to Scenario 2 is wrong. If I can admit to having ANY ONE ace, the probability that I have both is 1/3, not 1/5. That I don't state the suit of my admitted ace is irrelevant. If my ace is spades, there is no possibility of AH+2C, or AH+2D. If my ace is Hearts, there is no possibility of AS+2C, or AS+2D.
These sets of events are mutually exclusive and may not be totaled together to come up with a number of possible arrangements (just as AS+AH, and AH+AS can't be counted as two possible arrangements here).
Therefore, the statement "there are five arrangements of cards you could be holding" is false (except in the mind of the half-in-the-dark questioner - however, the problem isn't about what he thinks is true).
The possible pairs are:
Known+Unknown
ACE+2C
ACE+2D
ACE+ACE
And, the answer to the article's question is 1/3 as well (Argument 1).
Remember: The probability of a future event actually occurring doesn't change because someone asks questions and someone answers them.
It may help if you think of the admitted ace in terms of "My ace" and not "An ace".
Meanwhile, "Do you have the ace of spades?" (Are you looking at the ace of spades?) is the exact same thing as "Do you have an ace? Is it the ace of spades?" (Are you looking at the ace of spades?). And the questioner in Scenario 2 gleaned as much relevant information as did the questioner in Scenario 1, i.e., that AN ace was held. Suit is entirely irrelevant throughout the article. Knowing that the ace was spades (or hearts) in no way helps the questioner. The deck may as well have included two aces of spades, along with two non-aces.
(edit: Looking at -5, so far, against the hard facts of probability theory. Life is sweet. Please feel free to keep the denial coming. It makes me feel somehow saner with every negative vote. The article is an embarrassment, really.)