The condition of being in accordance with a norm. A problem relative to normality has arisen in recent times particularly in the life sciences. The difficulty of discovering normal traits has been compounded by an initial unsureness as to the way in which normality should be defined. Negatively, the normal is what is not abnormal, i.e., whatever functions at least sufficiently well to survive and to continue to function without requiring extraordinary assistance. Positively, two different norms have been proposed: the average norm, according to which the normal is what is characteristic of the greatest number; and the norm taken from the best, according to which the most perfect specimens are considered normal, all others to some extent falling short of normality. While each of the positive norms is easily reconciled with the negative, it is difficult to see how the positive norms are to be reconciled with one another, and hence to discover whether a given trait, admittedly not the best, should be considered normal or a falling short of the norm.
Types of Solution. Logically, the question of normality can arise only in a context of comparability, which involves in turn a multiplicity of similar things and also a judge to make the comparison. In a Platonic conception of the universe, the Ideas exist as the norms of all things. On any other hypothesis it is necessary to discover the norm. If the mind of the judge is taken as the sole source of the norm, either the norm is purely arbitrary, and hence of no scientific value, or the question recurs as a question about the nature of the mind itself. The source of the norm is therefore to be sought in nature as well as in judgment.
Several recent writers have noted that the question of determining the normality of anything, whether of the member of a species, the function of an organ, the mental state of an individual, or the working of a society, arises only in a context of means and end relationships.
Aristotle's Physics (192b 8–200b 9) supplies the elements of a solution to the problem of normality in the doctrine of causality, particularly final causality. For Aristotle, nature in this regard is "the principle and cause of motion and rest to those things, and those things only, in which she inheres primarily, as distinct from incidentally" (192b 21–23). Each natural thing, inasmuch as it has a definite structure, has a definite function possible to it. What is definite in nature is made so by final cause. Parts are parts of a whole that specifies them by constituting their end; organs exist for the sake of the function they perform; actions are defined by the end to which they are directed. Things have definite tendencies, and the definiteness of these tendencies is explainable in terms of their final causality.
What is normal, therefore, is what performs its function well: An organ is normal if it functions in such a way as to serve the whole body; an action is normal if it attains the end such actions are directed to attain. The end may be attained perfectly or imperfectly; but if it is attained, even badly or in an extraordinary way, the function is to that extent normal. Only an act that failed to achieve the end it was directed to could be called altogether abnormal. Thus the majority, over a long period of time, can be said to be normal at least to the extent of having what is necessary for mere survival; and in this way the average is the norm. And since it belongs to the very notion of the end to be a good, that which is most perfect, most in possession of its end, can also be said to be the norm. Thus the two norms, the average and the best, can be reconciled in the notion of the end.
Problems with Finality. There remains the difficulty of knowing the final causes of things. Certainly it is possible to infer from structure something of the nature of function; but no one has yet succeeded in defining even so common a natural being as a dog. The difficulty is particularly acute in the case of a human person, since the person as such is unique and incapable of being defined. Negatively it may be quite clear that a person is functioning inadequately in some respect; but normality in the positive sense would seem to be impossible to determine absolutely in the case of the person. Only on the basis of actual functioning can the person be said to be normal in his personal traits; and since the potentialities of a person can never be known with complete adequacy, it is impossible to say to what extent he is realizing them. Admittedly, the natures of many things are unknown to man; but in many instances one does know what things are for; and to the extent that it is possible to discern means-end relationships, and to that extent alone, is it possible to judge the normality of anything.
Objections against the proposition that the final cause constitutes the norm in natural things are directed principally against the possibility of knowing the final cause. descartes considered that on account of God's omnipotence and the weakness of the human intellect, it is impossible for man to know the final causes of natural beings, so that "what are called final causes are of no use at all in Natural Philosophy" (Meditations, 4). Evolutionists consider the evolution of new species an obstacle to the doctrine of natures in things. And historicity would replace human nature with history. A different objection, springing from the common confusion of final and efficient causality, need not be considered here.
The fact of human ignorance of the purposes of many things, and particularly of "external finality" (e.g., of the purpose of a frog), does not invalidate human knowledge of many instances of "internal finality" (e.g., of the purpose of a frog's eye), especially in biology, where the notion of adaptation, or organization for an end, is fundamental. Evolution, which rests upon the chance mutations of genes and selective reproduction, logically presupposes the existence of the "matter" of the new species in the genes of the old and also the basic lawfulness of nature, which Aristotle (195b 30–200b 9) has shown must underlie chance. The fact that human beings to some extent "make themselves" and make their culture argues for habit as "second nature" rather than against final cause. Explanation through final cause does not eliminate the usefulness of explanation through material, formal, or efficient cause. It merely makes evident the reason for the efficient cause's forming the matter in such a way as to bring about the desired result. Deficiency on the part of the other three causes, in turn, will result in partial or total interference with the attainment of a result that could be considered in reference to what was to be expected on the basis of the usual behavior of most individuals (the average norm) or on the basis of the behavior of those recognized as the best example of a group.
See Also: personality.
Bibliography: a. pompei, Enciclopedia filosofica, 4 v. (Venice-Rome 1957) 3:937. g. ambrosetti and c. negro, ibid. 934–37. m. k. o'hara, "Toward a Norm for Normality," American Catholic Philosophical Association. Proceedings of the Annual Meeting 36 (1962) 83–91. m. jahoda, Current Concepts of Positive Mental Health (New York 1958). c. smith, Contemporary French Philosophy: A Study in Norms and Values (New York 1964). e. l. fackenheim, Metaphysics and Historicity (Milwaukee 1961).
[m. k. o'hara]