assumes that the defenders have no signaling system, so that the play by west of (say) the 3 followed by the 2 does not signal a doubleton. During the course of many equivalent deals, East with KQ should in theory win the first trick with the king or queen uniformly at random; that is, half each without any pattern. Further accuracy A priori, four outstanding cards "split" as shown in the first two columns of Table 2 below. For example, three cards are together and the fourth is alone, a "3-1 split" with probability 49.74%. To understand the "number of specific lies" refer to the preceding list of all lies in Table 1. The last column gives the a priori probability of any specific original holding such as 32 and KQ; that one is represented by row one covering the 2–2 split. The other lie featured in our example play of the spade suit, Q32 and K, is represented by row two covering the 3–1 split. Thus the table shows that the a priori odds on these two specific lies were not even but slightly in favor of the former, about 6.78 to 6.22 for KQ against K. What are the odds a posteriori, at the moment of truth in our example play of the spade suit? If East does with KQ win the first trick uniformly at random with the king or the queen – and with K win the first trick with the king, having no choice – the posterior odds are 3.39 to 6.22, a little more than 1:2, in percentage terms a little more than 35% for KQ. To play the ace A from North on the second round should win about 35% while to finesse again with the ten 10 wins about 65%. The principle of restricted choice is general but this specific probability calculation does suppose East would win with the king from KQ precisely half the time (which is best). If East would win with the king from KQ more or less than half the time, then South wins more or less than 35% by playing the ace. Indeed, if East would win with the king 92% of the time (=6.22/6.78), then South wins 50% by playing the ace and 50% by repeating the finesse. If that is true, however, South wins almost 100% by repeating the finesse after East wins with the