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## 16 Peirce's rules of inference (Ad)## IntroductionPeirce's rules of inference can be used to reason with conceptual graphs. Here, we formulate the rules for conceptual graphs using the definitions we have just given. ## The rules- Erasure:
- Any evenly enclosed graph may be erased.
- Insertion:
- Any graph may be inserted in any oddly enclosed context.
- Iteration:
- A copy of any graph u may be inserted into the same context in which u occurs or into any context dominated by a concept in u.
- Deiteration:
- Any graph whose occurrence could be the result of iteration may be erased (i.e., if it is identical to another graph in the same context or in a dominating context).
- Double negation:
- A double negation may be drawn around or removed from any graph or set of graphs in any context.
## An axiom: The empty graphThe only axiom for Peirce's rules of inference is the empty graph. The empty graph says nothing about anything, and by convention is assumed to be true. ## Applying the rulesWhen one starts with a collection of conceptual graphs S and then
applies the rules to form another collection of conceptual graphs V,
we say that we have If we start with the empty graph and prove a collection of
conceptual graphs V, V is said to be a ## NextNext, we give an example of how to use the rules. Prev: 15 Definitions (Ad)Up: Part IV: Peirce's rules (Ad)Next: 17 Example of usage (Ad) |