The En Passant capture is a specialized rule governing pawn capture under very specific circumstances.  It is defined by the Federation of Internationale de Eches (FIDE) in Article 3.7 Section d of their Handbook of the Laws of Chess as follows:”A pawn attacking a square crossed by an opponents pawn which has advanced two squares in one move from its original square may capture this opponents pawn as though the latter had been moved only one square. This capture is only legal on the move following this advance and is called an `en passant` capture. This move must be made in the event that no other legal move is possible.” En Passant is French for “In (the pawn’s) Passing” or “How dare you not let me capture your piece” (sic).  It is believed that this rule was added to the formal rules of chess during the fifteenth century in southern Europe.  No one knows who invented it, or what governing chess body permitted it’s inauguration into the game.

The reason given for the addition of this rule is to restore a “balance of power” from a previous rule change.  Originally, pawns only had the ability to move one square at a time.  Therefore, if your opponent’s pawn made it to your fourth rank, then by moving your pawn one square on either adjacent file could result in its capture.  Since pawns can now move two squares on their initial move, the threat of an opponent’s fourth rank pawn can easily be thwarted by “sneaking” passed the threat to its adjacent square.  Since this is believed to be unfair, because not formerly possible, the en passant capture was invented.

There are a number of reasons that I believe the en passant capture is a major deviation from and blight upon the purity of the game of chess.  Let me begin by stating that implementing the en passant capture based upon the necessity of restoring a “balance of power” is completely erroneous.  The only time a “balance of power” would require restoration, is if a rule only applied to one side or player.  For instance, let us pretend that the chess world decided that since White was always privileged with the first move, that only Black could employ the two square pawn opening.  As ridiculous as that would be, giving Black an exclusive right when White has an exclusive right, would be an example of a rebalance of power.  However, since the same rules apply to both sides, (i.e., both sides have the right to move pawns two squares on each pawn’s first move, and both players have an equal opportunity to place their own pawns on their opponent’s fourth rank), there is no off-balancing of power which requires readjusting.

Secondly, the en passant capture was established based on the last known rule change in chess, (the two square pawn movement), over five hundred years ago.  It is impossible to fairly implement “rebalancing” rules without knowing with certainty, what the original rules of the game were.  No one knows for certain when or even where the game was invented, let alone what the original rules stipulated.  If you Google the word “Chess”, you will generate half a dozen theories on the game’s origin, (Persia, India, China, Africa, etc.), on the first page of results alone.  It is completely untenable to begin creating “rebalancing” rules after a thousand years of play, to adjust for supposed disparities.  If we knew exactly what the original rules were, we could systematically trace the evolution of the game and make intelligent judgments concerning where rebalancing was necessary.  As things currently stand, we cannot.

Thirdly, there are a number of rule changes that we are aware of, that never necessitated extraneous rule additions.  Unlimited range for Queens, Castling and unlimited range for Bishops represent three rule revisions which did not require or warrant “counter-balance” measures.  Therefore, just because a rule concerning piece movement or general play, changes, does not mean that the balance of the game has been corrupted.

Fourthly, unlike other rule changes, such as equipping the Bishop with unlimited range when it was previously limited to only two diagonal squares at a time, the en passant is a total aberration from the natural movement of pawns.  Since it applies only to capturing pawns, it is also discriminatory in nature and inconsistent.  If any other piece moved adjacent to the opponent’s fourth rank pawn to avoid capture, the rule does not apply.  It violates both the manner in which pawns move and the manner in which they capture, contemporaneously.  Furthermore, the en passant capture establishes the foreign precedent where an attacking piece need not land on or even threaten the square it is attacking in order to capture the opposing piece.

Fifthly, the en passant rule robs the players of the autonomy of making a perfectly legal move, whenever they desire, without fear of reprisal.  Supposedly, it is legal to move a pawn two squares on its initial move.  However, if my opponent’s pawn happens to occupy any square on my fourth rank, suddenly I am not permitted to avoid capture.  Either you have the right to move two squares or you do not.  It does not make sense to create arbitrary caveats to otherwise legal moves.

In conclusion, let me state that I have no delusions of turning the chess world on its head with my considerations here.  I am fully aware of the fact, that were I to participate in a chess club or tournament, that I would be expected to adhere to the rule of en passant.  If en passant is truly necessary, and my reasoning above is amiss, I vote to return to single square movements for pawns.  That, at least, is not a deviation from the foundation and movement methodology of the game.