The proof you cannot feel.

You will want to believe you are the exception. That other people leak, perhaps, but you — you are slippery, unreadable, a closed book. Nearly everyone believes this about themselves. And the belief is itself one of the most predictable things about us. The evidence is not kind to any of it. Begin with randomness, the thing you imagine you can produce on demand. You cannot. When researchers ask people to generate a random sequence — just say a string of numbers or heads and tails with no pattern — the results are reliably, measurably not random, and they fail in the same direction every time. People alternate too much. They switch when they should sometimes repeat, because a real run of three or four of the same thing feels suspicious, feels like a pattern, even though true randomness is stuffed full of such runs. We avoid repetition so consistently that our attempts at chaos have a fingerprint, and a trained eye or a simple program can spot the forgery in seconds. You cannot will yourself into a coin. The very effort leaves tracks.

Now bring that failure to the game. Across large numbers of players, the first throw is not a clean third each. People reach for rock more than chance would have them. Men especially, drawn to the fist, the aggressive shape, the one that feels like force. Before a single read has been made, the whole population has already leaned together in the same direction. And researchers have sat hundreds of people down and made them play this game for hundreds of rounds, recording every throw, and the pattern that fell out of the data was almost mechanical in its regularity. Winners tend to repeat the shape that just won. Losers tend to abandon the shape that just lost and rotate in a predictable direction. Win-stay, lose-shift. Not a handful of unusual subjects — the crowd, the same reflex firing in stranger after stranger, none of them aware they were doing it.

That phrase, none of them aware, is the whole danger and the whole point. These patterns do not survive in spite of being hidden from you. They survive precisely because they are hidden from you. You cannot correct a leak you cannot feel. And you cannot feel these, because they live underneath the part of you that believes it is the one making the choice. This is the hard floor beneath the entire game. Human beings are not random, cannot become random by deciding to be, and the ways we fail are lawful, repeatable, and measurable — which is only another way of saying they are exploitable, by anyone or anything that has learned where to look.