# System K2 (Sobociński)

[Hughes and Cresswell, 1996]

[Zeman, 1973]

**[Sobociński, 1964]**

**[Sobociński, 1964a]**

## Notes

Sobociński's K2

K2 is Ken Pledger's system 3q, and has distinct affirmative modalities
as follows:

p implied by Lp, p implies Mp
Lp implies implies p, LMp,MLp
Mp is implied by p, MLp,LMp
LMp is implied by Lp, LMp implies Mp
MLp is implied by Mp, MLp implies Mp

[Pledger, 1972, p270]
But that table contains a typgraphical error on this system. The above
has been corrected per [Pledger,
2000]

## Based on

The system K2 is the result of system S4.2
+ MS [LMp=>MLp]
[Zeman, 1973, p277]
[Hughes and Cresswell, 1996, p362]

The system K2 (3q) is the system S3 plus any of the
following:

{ MLLMp, MLMp, MLMMp, MMLMp } => { LLMLp, LMLLp, LMLp, LMMLp }

[Pledger, 1972, p275]

## Basis for

# Go to ...

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This page was last modified on July 15th, 2008