Hmmm, I would have said a probe is a forcing move, a double purpose move and a sente move normally

It is a move where you force the opponent to decide where he places his value on the board, and then you can act accordingly. If my opponent doesn't want the corner. I will live there, if he does, I have bonus aji to help me reduce or invade on the side instead, for example.

Probes are indeed difficult things.

Probes are played to see how your opponent will respond. There always need to be multiple answers for your opponent, else it's not a probe. Based on his response you then decide how to play out some other variation or situation on the board, usually leaving the probe move there as aji that can be exploited later. If you immediately follow up on your probe, it was more of an invasion, (one where your opponent could decide how to respond) and less of a probe. You will in this case likely end in gote and not have the advantage of deciding how to play out something else on the board, an advantage that is the main purpose of a real probe.

Example:

Click Here To Show Diagram Code

[go]$$B Corner
$$ ------------------
$$ | . . . . . . . . .
$$ | . . b W d . . . .
$$ | . . a X c . . . .
$$ | . . . , . . . . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

The white stone is a common probe, It usually is sente. It can maybe also be considered multi-purpose.
Now black has to decide what he considers most important by selecting a move between a-d. depending on blacks choice white can for example decide on a reduction or invasion somewhere else.

_________________
Laurens
Go school: freegame's Teaching School
Author of: The Next Move a book for 15-3kyu players.

臨機應變
i am not sure in chinese but this is characters we use in Korea.
and dictionary definiton is:
adaptation to circumstances ― act according to circumstances;adapt oneself to circumstances

probe is a skills you must have in order to be strong.
that is a skills that differentiate weak from strong.
i suggest you learn some simple probe for start and try to understand the concept if you want to go up in Rank.

edit: above example given by freegame is ok but little complicated. i suggest learn simple a or b example if you have hard time understanding it.

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

I have only experienced sudden jump down rather than up, especially after i read a book or studied kifu that different from my style.

_________________
长考出臭棋.

Simple example:

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 3 . . . . . O c . . . . . . b . . |
$$ | . . a O . . 2 . . , . . . O . O . . . |
$$ | . . . . . . . . 1 . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

The probe asks white "On which side do you want to make territory". Then says: "Oh this side? Well you can't have it."

Note that White would love to play at a if black didn't play 3, to make a huge corner. Black will later still have either a or b to deal with the upper right.

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . b . . . . c O . . . . . . . 3 . . |
$$ | . . . O . . . . . , 2 . . O . O . a . |
$$ | . . . . . . . . 1 . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

If white chooses the other side, then denies him too much territory there. Again, White would love to play a move like a to finish the corner, if black didn't play . And moves b an c are available to limit the potential of the upper left.

So by making the opponent choose a side first, black is able to play the proper invasion based on that information.

Another example:

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . a b . . . . . . 3 2 4 . . . |
$$ | . . . O . . . . . , . . . . 1 , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

Here is a common probe. White usually replies at a or b

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . 8 . 7 . . a . 3 2 4 . . . |
$$ | . . . O . . . . . , . . 5 . 1 , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

If you don't play the probe, but finish the joseki first, is a good move that threatens to invade at a while strengthening the corner.

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . 6 . . 9 . . a . 3 2 4 . . . |
$$ | . . . O . . . . . , . . 7 . 1 , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

If white responds to the probe with , then after the situation is better for black, because the invasion at a is no longer severe.

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . 6 . . 9 . . . 3 2 4 . . . |
$$ | . . . O . . . . . , . . . 7 1 , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

If white responds with , then black can choose the sequence up to , which doesn't leave the same invasion that the hanging connection would.

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . 8 . 7 . a . 3 2 4 . . . |
$$ | . . . O . . . . . , . . . 5 1 , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

If white foregoes the probe, and plays the solid connection sequence immediately, then white will play like this, and there is an invasion at a later.

So effectively, the probe is asking white to choose a move in the upper left first. Black can then determine the proper line of play in the upper right based on that extra information.

That was really enlightnening about probes. It will probably need a lot more experimenting and thinking to digest the information, but at least I have very good starting point. Thank you very much!

_________________
If you say no, Elwood and I will come here for breakfast, lunch, and dinner every day of the week.

Q 1: Yes. I made a big jump when I realized that I was playing too long in local regions. Simply realizing that I needed to tenuki more was a big help.

Q 2: There are so many go skills that being good in some areas can compensate for being bad in others, and the game is so long that a single error rarely produces a loss, except at the highest levels. Still, I think that weaknesses are more of a drag than strengths pull you up. My guess is that it is hard to play more than 3-4 stones stronger than your weakest area, and easy to play 9 stones weaker than your strongest area.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

If you can kill your opponents in the beginning, you have endgame skills.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

I experienced a large jump after a Yang workshop. I think most of it went over my head. One thing that stood out for me was the basic technique of when to typically extend or cut in a fight. That probably took me up 2 stones without knowing completely what I was doing. Granted, I was about 14kyu, and all jumps in rank seemed faster then.

Since then I've occasionally had epiphanies where I thought I suddenly saw things 2 stones stronger, but frustratingly could only play about a half stone stronger. I've learned to take what I can get (while striving for more)

Q1: Actually, I originally said that the only time I had an increase in strength attributable to a particular piece of knowledge. Now that I think about it, that's just the most recent example (though it was a while ago). It used to happen all the time as a DDK. And for beginners (20-30k), it's common for a single new piece of understanding to increase their strength by a couple stones. I mean, grokking that two eyes makes life (and why) obviously causes an increase in strength.

Looking back, I think I can attribute several stones worth of improvement to reading Attack and Defense for the first time as a DDK (though I felt like it was mostly over my head). I think people are just about always using hyperbole when they say such-and-such book made them two stones stronger. A&D really does (at least for players of the appropriate level).

Q2: I think it's *mostly* a "weakest link" situation. Like, I'm better at the opening and joseki than the average 4k, but my reading and direction of play is weak. So even if I get an advantage in the opening, I usually squander it.

@Herman: Those are the most instructive probe examples I've seen. At my level, I'm just starting to try probes but haven't really understood them well. Like I get that I'm supposed to choose my follow-up based on my opponent's response to my probe, but I usually don't have it worked out what those follow-ups might be. Those examples would be good candidates for a Sensei's page.

_________________
KGS 4 kyu - Game Archive - Keyboard Otaku

I enthusiastically agree. The best way to get from 10k to 9k is to stop making 12k mistakes

Maybe the two are coming together And bad aji too

- As 2kyu I read only very specific situations. Most of the skill is atomistic memorization. For example, making a safe extension from third line stone requires no thought; I already know that two spaces is the distance. Same goes to other useful shapes and tactics like capture races.

I think dan players exaggerate value of reading, because they have reached a point where memorization is no longer relevant. Memorization is very relevant to quickly get out of beginner class. I few simple principles did this to me.

how many instance in your game memorization actually help?
few opening moves and josekies perhaps..
rest of them are reading.

there are saying: "memorize joseki and the forget them"
you will forget them when you are strong enough and not have to rely on your memorization.
after that your reading will free you from boring josekies and you can create your own joseki or sometimes prove that existing josekies are wrong.
in my opening game of go is 99% reading.

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

By memorization, I think Toge is referring to a lot of the tools that you use to read. For example, knowing that placement tesuji often exist in a shape like 'x', or recognizing dead eyeshape and such. If I could manage to memorize every tesuji in every book, at least I'd have a better chance of seeing them.

I think that a reasonable metaphor is furniture. The serious person may like the idea of handmade furniture, and reject the idea of getting anything at all from a store. He may spend days turning out beautiful chairs and tables, far above what could be found in the local Sears.

However, there are two other options, not one. The option akin to pure joseki memorization is going to the store and buying a table. And you're right, that table is going to look like crap. =)

The alternative that Toge seems to suggest is to use memorization to get to the point where reading is useful and viable. Sure, we're going to the store, but we're going to buy hammers and saws.

I know this metaphor's not perfect, but I stand by it. Memorization is far from a full approach, but there is a lot to be said for the memorization used for shape/tesuji recognition. If I see a group on the second line, I want my mind to inherently think 'don't crawl', just because I've seen the results often enough to recognize them as bad.

Caveat: Tesujis and such require reading, of course, to ensure that the tesuji will work. One should never be without the other. I'm just saying it's hard to find the tesuji if you don't recognize the shape in the first place.

_________________
Someday I want to be strong enough to earn KGS[-].

- Quite a lot:

* Opening principles
* Joseki
* Extensions
* Whole-board evaluation
* Types of connections
* Types of tesuji
* Capture race principles
* Dead shapes
* Probes
* Forcing moves

These on the top of my head. A 20k is not 20k because he can't read. He's 20k because he has no idea what to read. Everything that happens in a game for him is unexpected. Playing many games allows situations to repeat and in those occasions learning happens. You need to brune that tree of possibilities to a few relevant moves, which you can then read in-depth using relevant counter moves. That's what strong players are doing.

* Opening principles = reading
* Joseki =memorization + reading.
* Extensions = reading
* Whole-board evaluation = reading
* Types of connections = reading
* Types of tesuji = reading
* Capture race principles = reading
* Dead shapes = there are only few dead shapes. getting to dead shape is reading.
* Probes = reading
* Forcing moves = reading

get my point?

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

- That's from your point of view. After taking all atomistic knowledge you have for granted.

Analogy:
To type a sentence, you have to understand what each word means. Typing a sentence here is production. Arranging words in correct order to have meaningful result. In order to type a sentence, you don't need to invent any words. They're all in dictionary. You've heard all the words you're using somewhere before. That's knowledge. Same goes to game of Go: you hear the proverb "hane at the head of two stones is a good move" and the first move you'll consider in situation like that is hane. This knowledge makes weak players stronger.

i play hane at the head of two stone because i read what happens after not because i memorized it.

_________________
"The more we think we know about
The greater the unknown"
Words by neil peart, music by geddy lee and alex lifeson

Going to one extreme:

A program which memorized all the pro games, all known joseki, all standard shapes and their weaknesses, all proverbs, all strategic concepts, etc... But it is not able to read one move further. Such a program cannot be strong because it will be destroyed with the first slighest
deviation from a joseki, for example.

To the other extreme:

A computer program just being able to apply the rules and search the move-tree in depth. Despite the enormous reading ability, such a computer program cannot be strong because it lacks two vital skills:

1- It does not know what to read: This can only be irrelevant if the reading power is infinite. But for being realistic, we have to assume it is not infinite and it cannot search the complete move tree.

2- Even if it reads the correct move and every possible follow-up, it still does not know how to assess the result of his reading.


My conclusion:
One without the other (memorization and reading) is useless.

_________________
If you say no, Elwood and I will come here for breakfast, lunch, and dinner every day of the week.