Creating Tableaux By Hand

1
Creating Tableaux By Hand
To show TD, TDgtBP, BPgtBD BD
1. Start a tree with wfps labeled T or F
TTD, TTDgtBP, TBPgtBD, FBD
TBD
2. Add nodes by reducing non-atomic wfps acc. to
Wang rules.
TBP
FTD
X
TBD
FBP
3. Close any branch that contains Tp and Fp.
X
X
4. If all branches close, root is unsatisfiable.
2
Tableau For a Contingent Wfp
To show TDgtBP, BPgtBD BD
TTDgtBP, TBPgtBD, FBD
TBD
TBP
FTD
TBD
FBP
TBD
FBP
X
X
X
A complete, but unclosed branch is a satisfying
model of the root.