The bishop is superior to the knight.

Pinning and Skewering PotentialMy opponent has conceded these two points, seeing as how the knight is incapable of performing either a pin or a skewer. The most he did to deflect these points is compare their usefulness to forks, but the fact of the matter remains: a bishop can perform both a pin and a skewer, while a knight can perform neither.And I think my previous rounds have shown just how important these tactics are regardless of how important (or unimportant) forking happens to be.Forking PotentialI do concede the knight is more dangerous in its ability to fork, but the point cannot be entirely awarded to the knight seeing as how the bishop can perform a fork (it can do so only with a bit more difficulty and preparation than a knight, but the point is it can do so). The bishop may need another piece protecting it in order to fork certain opposing pieces (such as the queen), but if you're not protecting your own pieces in a game of Chess, then what are you doing?Checkmating PotentialMy opponent tries to tell us that it is, in fact, possible to force a checkmate with nothing save your king and a couple knights. However, this is simply untrue. International grandmaster Edmar Mednis described the knights inability to force checkmate as "one of the great injustices of Chess". [1]If we look at Torvald's first diagram, we can see that the position is not actually checkmate, but stalemate, since the king is not even in check. This is to say that if the king could simply not move on Black's next turn, it wouldn't be captured. However, the king is the only piece Black has left, so it must move. The only places it can move to, though, are places which it can be captured. Moving your own king into check is an illegal move, but since these are the only moves left available, the game ends in a stalemate due to lack of a legal move. The first diagram does not show White winning, but Black and White coming to a draw.I admit, I should have gone into more detail earlier when I said two knights (and a king) can't force a checkmate, because Torvald's second diagram does appear to be checkmate. In fact, it is. There are ways to manually set up the pieces on a chessboard to create a checkmated position with just two knights and a king. But in a real game, when your opponent actually gets to decide where to move his own pieces, you will not be able to checkmate him (unless he makes a mistake).Where, for instance, do you suppose Black's last move was in Torvald's second diagram? Or the move before that? The only way for Black to find his king in such a surrounded position is by allowing it to happen. Earlier, if he had tried moving his king toward the center (before the opposing king or one of the knights became so close) he would have been quite safe.In light of all this, I shall clarify the point I was making: it is impossible to force a checkmate with only two knights against an opponent with an ELO rating higher than 600.Two bishops, on the other hand, can force a checkmate no matter how skilled or knowledgeable the opponent is (see earlier source).Torvald's EvaluationTorvald has suggested his own method of determining relative value (or "attack ratio") of Chess pieces by dividing the maximum number of spaces that are able to be threatened by the number of pieces which can retaliate if threatened.The bishop, for instance, can threaten 13 spaces simultaneously at most. And the number of pieces which can capture it if threatened by it are two (the bishop and the queen). Therefore, dividing the former by the latter will get 6.5, its relative value.The knight can threaten 8 spaces at most, and the only piece that can retaliate its threats is another knight. 8 divided by 1 is 8 (about 1.2 times higher than the bishop).This method might seem intuitive at first, but just look at the "attack ratio" of the rook: 7 (lower than the knight!). Surely there is no dispute which is more valuable, the knight or the rook? I've seen many evaluations of grandmasters charting the relative values of pieces (like those Torvald was trying to appeal to in round 2) and I've never seen a knight praised more highly than the rook. Unless my opponent is willing to admit that the knight is also more valuable than the rook, we can excuse his method as inaccurate. However, doing so may cast doubt on his knowledge of Chess altogether.If we must do anything with Torvald's numbers, it may be to multiply them, not divide them. Multiplying the maximum number of spaces that can be threatened by the number of pieces that can be threatened without retaliation will provide us with the relative likelihood each piece has to successfully threaten other pieces (and therefore show us its relative value at least as an attacking unit).Queen: 135 (only the opposing queen is guaranteed to have the chance to retaliate)Rook: 56Bishop: 52King: 40 (eight spaces to threaten times four pieces to threaten without retaliation; the king cannot threaten to capture the queen or the other king, else it would put itself in check)Knight: 40Pawn: 4 (the only two pieces a pawn can threaten without retaliation are the rook and the knight)I won't claim this to be a perfect method, just one that is likely more accurate than Torvald's.Thank you, Torvald, for a fun and interesting debate. And thank you, audience, for taking the time to read it. Vote for who you think provided the most persuading arguments.Source:[1] Advanced Endgame Strategies (Mednis, 1996)