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Practical Reasoning

Disciplines > Argument > Practical Reasoning

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.

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?