Steno-Chess

Steno-chess (SC) proposes itself to play with a series of simple chess instructions, assembled in a character string.

Example of such a string : ghLxLR3xo#

Here is the complete SC instruction set (all the traditional chess rules are kept):

a = occupy a square on the a-file (either capturing or not)

b = occupy a square on the b-file (either capturing or not)

c = occupy a square on the c-file (either capturing or not)

d = occupy a square on the d-file (either capturing or not)

e = occupy a square on the e-file (either capturing or not)

f = occupy a square on the f-file (either capturing or not)

g = occupy a square on the g-file (either capturing or not)

h = occupy a square on the h-file (either capturing or not)

1 = occupy a square on the 1-rank (either capturing or not)

2 = occupy a square on the 2-rank (either capturing or not)

3 = occupy a square on the 3-rank (either capturing or not)

4 = occupy a square on the 4-rank (either capturing or not)

5 = occupy a square on the 5-rank (either capturing or not)

6 = occupy a square on the 6-rank (either capturing or not)

7 = occupy a square on the 7-rank (either capturing or not)

8 = occupy a square on the 8-rank (either capturing or not)

P = play a Pawn (either capturing or not)

R = play a Rook (either capturing or not)

N = play a Knight (either capturing or not)

L = play a Bishop (either capturing or not  L stands for the german Lδufer)

Q = play a Queen (either capturing or not)

K = play your King (either capturing or not; castling allowed)

x = make a capture (en passant or not)

% = make an en passant capture

~ = play a move (a legal move, of course  as all moves here)

+ = put your opponents King in check (simple check, double check, discovered check, or by promoting a pawn)

= = stalemate immediately

# = checkmate your opponents King (directly or by discovered check)

o = castle to the kingside

0 = castle to the queenside

r = promote a Pawn into a rook

n = promote a Pawn into a knight

l = promote a Pawn into a bishop

q = promote a Pawn into a queen

[One will keep in mind the difference between o and 0]

A string is read left to right. Odd instructions are for White, even instructions for Black.

Now, let us look again at the example on top of page. The string ghLxLR3xo# should be read like this (in absence of other indications, the string of instructions starts with the first move) :

White has to move a piece in order to occupy a square on file g (either capturing or not)

Black has to move a piece in order to occupy a square on file h (either capturing or not)

White has to move a Bishop (either capturing or not; either giving check or not)

Black is forced to make a capture somewhere on the board (x)

White has to move a Bishop (either capturing or not; either giving check or not)

Black has to move a Rook (either capturing or not; either giving check or not)

White has to move a piece in order to occupy a square on rank 3 (either capturing or not)

Black is forced to make a capture somewhere on the board (x)

White has to castle on the kingside (o)

Black has to checkmate his opponent (#).

Steno-Chess is not a new standard for describing chess positions; its aim is to play with strings of instructions which may seem, at first glance, weird or contradictory.

As one will quickly notice, the standard ASCII SAN notation (or even the Chess Informants) can lead to several SC strings. For example, the short game:

1.g4 h5 2.Bg2 hxg 3.Bxb7 Rxh2 4.Nh3 BxB 5.0-0 Rh1#

... could produce, among others, SC strings like ghLxxR3xo1, 45ghLxNLoh or ghLxLR3xo# (the latter being the one which opens the page).

The aim of Steno-Chess, in reality, is to play with the assumed blur of its own set of instructions.

How about, for instance, trying to replay the following game? But take care: the seemingly haziness attached to some moves disappears when you look further in the string. Every move is forced, in fact  and this is the beauty (?) of the exercise:

dg6LxgxK+x5Nx4+NxLgx+N1+x2xg+5ebxR6+dQNQg4~#

Something else. Nicolas Graner (a friend of mine) warned me, when we had our first discussion about SC:

With your system, it is impossible to describe the move < 1.a3 > because the notation < P > doesnt fit (too ambiguous  there are eight possible pawns), neither < a > (three movements are possible, bringing a piece on the a file), nor < 3 > (twelve movements  between Knights and Pawns  fulfil the requirement of occupying a square on the 3-rank

Ive answered him that SC are not to describe a game or a standard sequence of move (as we have seen), but to build labyrinths through which only one path leads to the exit. Nicolass remark, however, was still challenging me... So I tried yesterday (February 29th, 2004) to find SC strings (the shortest ones) in order to fix all the twenty white moves which can open a real game.

Here is the (almost) full display. A single line should be read like this: If you obey the string at the right of the arrow, you cannot play another first move than the ASCII one at the left.

1.a3 > 3e2x

1.a4 > ab3x

1.b3 > be33

1.b4 > b~5

1.c3 >  ?

1.c4 > cb5x

1.d3 > 3gK+

1.d4 > dex

1.e3 > 3f+

1.e4 > 4f+

1.f3 > 3~~#

1.f4 > 4Nf+

1.g3 > gd23

1.g4 > g~5

1.h3 > 3d2x

1.h4 > hg5x

1.Na3 > a~1

1.Nc3 > c~1

1.Nf3 > f~1

1.Nh3 > h~1

Here is (march 4th, 2004) the same exercise for the first twenty black moves:

1. ...a6 > NaNx

1. ...a5 > bax

1. ...b6 > ab5x

1. ...b5 > abx

1. ...c6 >  ?

1. ...c5 > bcx

1. ...d6 > c6+

1. ...d5 > cdx

1. ...e6 > ~6~#

1. ...e5 > dex

1. ...f6 >  ?

1. ...f5 > efx

1. ...g6 > hg5x

1. ...g5 > fgx

1. ...h6 > NhNx

1. ...h5 > ghx

1. ...Na6 > eNx

1. ...Nc6 > ~c~8

1. ...Nf6 > ~f~8

1. ...Nh6 > dNx

We will leave to the reader the pleasure of finding the 4-symbol strings above which were replaced by < ? >. Answers will be posted soon here...

We would be delighted if some composers should adopt the Steno-Chess notation. This would enrich the beautiful domain of no-diagram chess (link in French).

__________

Thanks to Gilles Esposito-Farθse for his remarks and for suggesting me the % symbol. Many thanks too to Mario Richter who suggested me a lot of improvements in the English notation of promoted pieces  and for allowing the King to castle when it has to obey the K instruction! Mario checked and corrected a lot of the above strings  thanks again! Thanks too to Olivier Pucher for the = symbol and for his enthusiasm in playing with SC strings (see here). Finally, thanks to Antoine Fourriθre for having recorded SC on the ChessVariants server  and for having re-worded in good English the above rules!