Peter Tillers makes the excellent observation that “[f]undamental theoretical considerations and differences lead to different mapping strategies.” http://groups.google.com/group/rationale/browse_thread/thread/2baf32ff6d3c417e. This is certainly true. When attempting to persuade a judge or jury, however, a mapping strategy and underlying argument schema that is intuitively obvious to non-scholars at first impression is indispensable.

For years, I have used argument maps in briefs and as trial exhibits. A mapping strategy that requires explanation or demands a significant cognitive load of the judge or jury can actually do harm to the case. This is because generating confusion in the adjudicator due to the complexity or lack of rigor of the mapping strategy reduces credibility of the advocate. And the advocate, and ultimately their client, is blamed for the discomfort of the confusion.

This is why modeling all inference (e.g. deductive, inductive, and abductive) as a function of transitivity, as in Inference Path mapping, has been, in my litigation experience, so successful. Adults’ ability to chain together long strings of transitive inferences is so “unbounded” that it has been named “inferential promiscuity.” http://www.ling.ed.ac.uk/~jim/litloe.pdf. Evidence suggests that people can even make these transitive inferential connections without conscious cognitive processes or explicit logical reasoning. http://faculty.virginia.edu/levylab/Publications/script/Hippocampal/Hippo%20TI/Greene_et_al2001.pdf; http://psych.colorado.edu/~oreilly/papers/FrankRudyLevyOReilly05.pdf. Transitive inference has even been displayed in a variety of animal species. http://www.cs.helsinki.fi/group/cosco/Teaching/CoscoSeminar/spring2007/articles/watanabe-2006.pdf. (So, perhaps, you can test out your Inference Path maps with your pets.)

The previous post illustrated that, for the same argument, Inference Path mapping  produces a smaller proposition and argument density than Hierarchical Pyramid mapping. This condensing increases readability. http://jac.gsu.edu/jac/6/Articles/4.htm. Readability is also increased, in my opinion, through consistently structuring premises in a transitive manner even without multiple reason layers.

The following is a simple self-test of readability comparing different argument schemas. The Rationale maps on the left-hand side use conventional scaffolding and are examples from Austhink (the leader in argument mapping). The Rationale arguments maps on the right-hand side are the same argument depicted as a precise transitive inference using an Inference Path. To create a precise transitive inference the advocate simply ensures that the subject of the main contention is joined to its predicate by a series of interlocking sentences in a transitive path as illustrated below. (A smaller descriptor than a predicate can also be sequenced in a transitive path as illustrated in the final comparison.)

Following this transitive rule, the advocate is never unsure whether co-premises are linked or whether there are missing co-premises.

Which argument maps below do you think would be more readable to the mapping uninitiated judge or jury? Sometimes the difference may seem slight (particularly if you are already skilled in reading argument maps), yet, in litigation why not maximize the persuasive effort and minimize confusion.