Practical reasoning

Disciplines > Argument > Practical reasoning

Necessary condition schema | Critical questions | See also

Douglas Walton (1990, 1997) has described a simple schema and set of questions by which reasoning may be rationally undertaken.

Necessary condition schema

Walton describes a Necessary Condition Schema based on a set of premises by which practical reasoning may be achieved:

• Goal Premise: My goal is to bring about A.
• Alternatives Premise: I reasonably consider on the given information that bringing about at least one of [B0,B1,...,Bn] is necessary to bring about A.
• Selection Premise: I have selected one member Bi as an acceptable, or as the most acceptable necessary condition for A.
• Practicality Premise: Nothing unchangeable prevents me from bringing about Bi as far as I know.
• Side Effects Premise: Bringing about A is more acceptable to me than not bringing about Bi.
• Conclusion: Therefore, it is required that I bring about Bi.

Critical questions

Questions that may be used to resolve these premises include:

• Alternative Means Question: Are there alternative means of realizing A, other than B?
• Acceptable/Best Option Possible Question: Is B an acceptable (or the best) alternative?
• Possibility Question: Is it possible for agent a to do B?
• Negative Side Effects Question: Are there negative side effects of a's bringing about B that ought to be considered?
• Conflicting Goals Question: Does a have the goals other than A, which have the potential to conflict with a's realizing A?

See also

Walton, D. (1990). Practical Reasoning: Goal-Driven, Knowledge-Based, Action-Guiding Argumentation, Rowman and Littlefield, Savage Maryland, p48

Walton, D. (1997). 'Actions and Inconsistency: the Closure Problem of Practical Reasoning', in Ghita Holmstrom-Hintikka and Raimo Toumela (eds.), Contemporary Action Theory, Vol. 1, Kluwer, Dordrecht