Sentence pattern:If [S 1 then S3] and if [S
2 then S4]Either [S1] or [S2] Therefore, either [S3] or [S4] |
Form: |

Example:If it's gold then I'm rich and if it's pyrite then I'm poor. It is either gold or pyrite. Therefore, eithe I'mr rich or I'm poor.. |
Example symbolized:Following the logical convention of letting a single letter represent an atomic sentence:G = It is gold.. Y = It is pyrite. R = I am rich. P = I am poor. And replacing ' if...then...' with a symbol for implication: > And replacing ' either...or...' with: +And replacing 'and' with: . (G > R) . (Y > P) G + Y ------------------ R + P |

Example of CD:[(P = Q) > ~X] . [(S = T) > ~Y](P = Q) + (S = T) ---------------------------------------- ~X + ~Y |
1. (X = Y) + (W = Z) 2. [(X = Y) > K] . [(W = Z) > P] 3. (K > S) . (P > T) / S + T 4. K + P 1, 2 CD 5. S + T 4, 3 CD |