About The Value of the First Move
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To play, or not to play?
In Go, the placing of a stone is an important part of playing the game. Players have the ability to "pass"... however, the indication of "winning" and "losing" is only apparent if there are go stones on the board.
A move has the potential to influence every other position on the board. The evaluation of this potential is dependent on:
- the ability to "connect" with any target position,
- "dominance" over potential (and real) opponent stones,
- "flexibility" of goals/aims/strategy to counteract the goals/aims/strategy of the opponent.
(These are the main ideas behind all the terminology used in Go)
The fact that stones can be added anywhere on the board (except for where other Go stones already exist or suicide moves with no purpose), combined with the sheer size of the Go board; means that according to combinatorics, there are a huge PossibleNumberOfGoGames. If the purpose of the Game of Go is to "win", then every possible combination of events on a Go board is filled with "bad moves" and "illogical sequences".
"Perfect Play" is a theoretical idea (according to a set of rules) which predicts either a win or at worst a tie, irrispective of the moves played by the opponent. "Perfect Play" has a complete command over every single possible game where all the moves made are the highest value possible with no uncertainty. For perfect play to be used in a situation, it must be possible to win or tie if the opponent attempts "almost perfect play" (for some non-go games, simply going first can result in losing the game with two player perfect play e.g:21 matchstick challenge).
The 21 matchstick challenge is a young children's game where the "winner" is the person to take the last matchstick. The rules are simple: Simply take either one or two matches from the stack -- then it's the opponents turn.
The calculation required for the various lines of "Perfect Play" using "tree search" evaluation is immense. Human beings are limited creatures, so there is a fair deal of LuckInGo... but humans tend to play quite well (although not perfect). This is because (instead of reading every single sequence combination) most of the time, mental tools and logical shortcuts are applicable to a greater number of situations.
The purpose of this page is to describe different ways of thinking about how to evaluate a go move. Varied techniques are encouraged to be shared here...
A long game starts with a single move
The first move on the board by Black sees a total of 55 possible opening plays (eliminating differences in rotation and transposition).
+ The first move gains an unchallenged board position.
+ The starting player is always either equal to White in moves played or one ahead. (Making objectives slightly easier with balanced play)
? It presents the start of the game for the second player.
- The first player reveals his/her goals and strategy first.
Depending on Black's choice of move, White has a varied number of responses (eliminating differences in rotation and transposition). A Black tengen play maintains symmetry throughout the board.
![[Diagram]](../../diagrams/36/fdc859170763bd2d689a1d305bb01c77.png)
White response to tengen; 54 possibilities
? White stone is closer to the edge of the board than the Black stone
- White has less possible choices of moves than Black had.
If Black plays on a diagonal or vertical/horizontal point of symmetry, half the board is still the mirror image of the other half.
Same situational outcome as the previous diagram.
The remaining Black options create an instant asymetrical relationship with the board.
The 3rd move has a maximum of 359 different positions. No stone is able to be captured until this move. Absolute symmetry is broken for the moment due to the fact that the White and the Black stone aren't the same colour...
this section for revision
The biased see-saw of advantage/disadvantage of Black's first play visually decreases as more stones are added to the board. Inequity can be found when contemplating the outcome of a board position in the mid-game. Every single move during the game was ever so slightly biased by Black's greater command play by play.
Komi
Komi is the artificial compensation White receives for playing second. But is it really indicative of the advantage Black gains by going first?
A study in relation to joseki
If there is one thing joseki can teach us, it is how moves pertaining to a local situation are weighted proportionally. There are thousands of joseki, with new ones being analysed all the time. From any of them, however, you should be able to find the same evidence of moves that are weighted proportionally to each other.
![[Diagram]](../../diagrams/48/69f520767088a64c882de3190de1a2a0.png)
One of the continuations of the taisha joseki.
Pictured to the left is an example of one of the many continuations of the taisha joseki played out on a 9x9 board.
With black 10, the joseki is finished, with white to play to next move. Since each move has been proportional to the opposing players previous move, the groups that have been formed are, thusly, proportional to one another.
So, what does this mean? Well, if joseki is any indication of proportional moves, then this game should be able to proceed from this position to a fairly even end result.
Have a try yourself! Oh, and don't forget to add Komi for white ;)
Note: This page is intended to describe different ways of thinking about how to evaluate a go move without going into actual numbers or examples. It is intended to later create sub-pages (or reference external pages) of examples when this page is completed. At the moment, the edits are attempting to be thorough and consistant.
Subnote: there is much superflous information that may impede succinct paragraphs... they will need to be sub-paged (later)