In the episode Checkmate No.6 is told the way in which to distinguish between the blacks and the whites on the chessboard, they looking all the same, you judge by attitudes, you soon know who's for or against you, the same way as it is in life, it's simple psychology.
When I was a lad, I was in a gang once, oh not the type of gang you get today, one carrying guns, although we did carry guns, cap guns, and spud guns, you pushed the barrel of the gun into a potato, then fired the little pellet created in the barrel, all pretty harmless stuff. But every gang must have a leader, and so it was with ours.....you will recall with No.6's gang, that it was he who took charge and did everything, apart from constructing the radio transmitter. You will recall that it was No.6 who dashed off to see what was wrong upon hearing the distress signal stop, and leaving his men behind. If only No.6 had taken one man with him, he could have sent the other man back to the Green Dome to tell the others what was happening, and himself put out to sea on that pair of rubber lilos sending the distress signal, and bring in the ship. But he didn't. No.6 was brought to reckoning by the Rook who put to No.6 his own test. We eventually turned on our gang leader because he wouldn't let any other memeber of the gang do anything, because he simply didn't trust us enough! BCNU