RoShamBo strategies attempt to predict what the opponent will do. Given a successful prediction, it is easy to defeat the opponent (if you know they will play rock, you play paper). However, straightforward prediction will often fail; the opponent may not be vulnerable to prediction, or worse, they might have anticipated your predictive logic and played accordingly. Iocaine Powder's meta-strategy expands any predictive algorithm P into six possible strategies:
P.0: naive application Assume the opponent is vulnerable to prediction by P; predict their next move, and play to beat it. If P predicts your opponent will play rock, play paper to cover rock. This is the obvious application of P.
P.1: defeat second-guessing Assume the opponent thinks you will use P.0. If P predicts rock, P.0 would play paper to cover rock, but the opponent could anticipate this move and play scissors to cut paper. Instead, you play rock to dull scissors.
P.2: defeat triple-guessing Assume the opponent thinks you will use P.1. Your opponent thinks you will play rock to dull the scissors they would have played to cut the paper you would have played to cover the rock P would have predicted, so they will play paper to cover your rock. But you one-up them, playing scissors to cut their paper.
At this point, you should be getting weary of the endless chain. "We could second-guess each other forever," you say. But no; because of the nature of RoShamBo, P.3 recommends you play paper -- just like P.0! So we're only left with these three strategies, each of which will suggest a different alternative. (This may not seem useful to you, but have patience.)