Unconditional life

  Difficulty: Intermediate   Keywords: Life & Death, Go term

Chinese: 净活 (jing4 huo2, "unconditional life")
Japanese: 無条件生き (mujōken iki, "unconditional life")
Korean: -

The terms unconditional life and unconditional death are somewhat ambiguous and can mean different things depending on context.

Simple usage

In the most common usage, generally found in tsume-go, unconditional precludes conditions such as ko. Such solutions are normally preferred over those that depend on ko. Seki is usually acceptable.[1]

[Diagram]
white to kill unconditionally  
[Diagram]
failure, result depends on ko  
[Diagram]
success, unconditional death  

In the example above, the first solution is considered a failure, because it does not kill unconditionally. The outcome depends on a ko. The second solution is considered correct, as black dies unconditionally.

This meaning is often simply referred to as Alive (or Dead)

Stricter usage

In research articles, unconditional life sometimes means alive even if the defender continues to pass. This is opposed to alive, unless the defender continues to pass. Here the condition is alternating play. This usage of unconditional life can be helpful for beginners to understand the concept of alive. It is also the common usage in more scientific approaches of life and death issues in game positions, e.g., in articles that lay a base for computer algorithms such as Benson's algorithm, but it can be used in ordinary game discussions too.

This meaning is also referred to as Pass-alive, absolute life or invulnerable.


[1] In cases where seki is not acceptable (i.e. where a player must be able to make a two-eye-formation), the term independent life is sometimes used for extra clarity.

More at /Discussion.


Unconditional life last edited by MrTenuki on March 29, 2012 - 18:09
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library