This chapter has described various procedures, in addition to the rational application of norms to cases, to follow in the quest for moral truth. It might be supposed that some of these could be used to commensurate premoral goods and bads, thus making proportionalism a workable method of moral judgment. But that is not so.
Proportionalists might imagine that the methods of criticizing emotions and discerning described here provide what they need to commensurate the goods and bads involved in different possible courses of action. However, these processes are not what proportionalism projects. They are not an attempt to commensurate various instantiations of goods that provide the reasons for free choices, but are concerned with criticizing emotions or perceiving the harmony of various groups of emotions with one another. If some set of emotions were to be used as a standard for selecting among options (as is rightly done in discernment) before making sure the options pass all rational tests (as must be done before discerning), one would in fact be accepting the maxim: abandon reason and follow emotions. That is not a moral norm but a recipe for immorality (see S.t., 2–2, q. 47, a. 6).
The treatment of conflicts of duties as well as several other segments of this chapter can be used to illustrate several different and legitimate senses of proportionate reason as it is used by traditional moralists. They said, for instance, that a proportionate reason is needed in order to accept bad side effects or divide goods unequally among members of a group entitled to share in them. The responsibility not to violate a moral absolute is a proportionate reason for accepting any side effects of avoiding its violation, however bad. The promotion and protection of basic human goods is a proportionate reason for sacrificing instrumental goods. Any moral responsibility to do something is a proportionate reason for accepting the side effects, provided accepting them is not conditioned by emotional motives unintegrated with reason, for instance, motives involving partiality. The discerned appropriateness of fulfilling one of two conflicting duties, assuming all prior tests have been passed, is a proportionate reason for not fulfilling the other.
The account of proportionate reason provided here is in perfect continuity with the tradition.
First, it makes it clear why classical moralists never supposed anyone could have a proportionate reason for violating a moral absolute. Insofar as the classical notion of proportionate reason depended on taking emotions into account, it was limited in application, for classical moralists realized that emotions, no matter how well integrated with faith and personal vocation, never can justify a choice to act against reason. Thus, as is done here, the classical moralists invoked proportionate reason only after other rational tests had been met.
Second, in offering the standard of proportionate reason, these moralists assumed that it would be applied by Christians of some maturity and integration: prudent persons who would intuitively apply the standard of their well-integrated emotions. That also is why it often is suggested that the example of good and experienced people be consulted to see what reason would be proportionate.