The primary objective of this investigation has been to examine informal reasoning – to examine how people reason about real, complex issues of genuine importance, issues they are likely to have occasion to think and talk about in their own everyday experience. This objective has been realized. We found that people were able to communicate their thinking on such topics effectively and often in considerable detail. It was clear that most had indeed thought about these issues before, and they were able to articulate coherent causal theories pertaining to them, some of them of considerable complexity, and to discuss their theories in response to the questions posed to them.

The informal reasoning examined in this book has been cast in the framework of argument. In this final chapter, our findings regarding people's argumentive reasoning skills are summarized. The implications of these findings are then considered from a number of disciplinary perspectives. Finally, we consider the significance and the possible means of helping people to reason better.

THE SKILLS OF ARGUMENT

Although we observed great variability in people's mastery of them, the argumentive skills that we have examined are clearly only of the most elementary sort – preconditions, almost, for rational argument of either the rhetorical or dialogic form. These elementary skills of argument can be summarized as entailing the ability to contemplate whether what one believes is true, in contrast simply to knowing that it is true.