Can Qualities Be Measured?

CAN QUALITIES BE MEASURED? DEVELOPMENT in modern experimental science began at the moment when qualities were measured; and the basic factor of progress in such science has been advancement in measuring qualities. It is impossible in our day to think of experimental science except in terms of measuring heat, light, weight, voltage, valence, radiation, emotion, sensation, intelligence, behavior, and other like entities. While science has preserved much of its ancient naturalistic and qualitative character, it has advanced, nevertheless, by increasing measurement and quantitative treatment of the beings which in other times were qualitatively analyzed and described. Such measurement has produced undeniable results; and theories which have their foundation in measurements have been successful in predicting future phenomena. This indicates that the process of measuring qualities is valid. For the philosopher of science, therefore, questions are bound to be raised which are the theoretical foundation of measuring qualities: Are such qualities truly measurable? If they are so, why? Are there any limitations to the measurability of qualities ? Finally, how does one measure them? These are fundamental questions. For, if it is true that qualities cannot truly be measured, then the scientist is engaged in an illusory enterprise. And further, if there are limitations which accompany measurability in qualities, then these restrictions will necessarily condition the truth, the meaning and the accuracy of the measurements; and make it necessary to modify, restrict, and interpret the use of data obtained under such limitations. Adequate solutions to these problems of measurability in qualities may be reached by an application of several principles 31 32 MARK HEATH of the philosophy of nature of Aristotle and St. Thomas Aquinas. Concerned with such application this study first considers the act of measurement and those properties which it requires in the object to be measured. It establishes that these properties are present in qualities-but with limitations; and concludes that under these restrictions, qualities are measurable . Finally it treats the problem of direct and indirect measurement of qualities. I. ON MEASURABILITY IN GENERAL 1. The Nature of Measure and Measurability Measure, says Aristotle, is that by which quantity is known.1 This is the fundamental and truest meaning of the word measure. It includes a "means of knowing" and "quantity." Measure is the determination and estimation of quantity. "... Measure is found first of all in numbers, secondly in magnitudes ." 2 It is properly spoken of in quantities, says St. Thomas, for measure is that by which the quantity of a thing is made known.8 The use of the term measure is extended by analogy from its basic meaning, however, to include any norm which may be applied in any genus: " Measure is found first of all in numbers, secondly in magnitudes, and in a certain other way in all other genera, as it appears in IX Metaph." 4 Measure may reach beyond the quantitative aspect-thus any object is judged to be a more or less true species of a class, according as it approaches or recedes from the ideal of the class. It is said thus to be measured by the ideal. This is true of whiteness, intelligence, courage, and societies. Men "measure up" to the standard and are judged as true members of a class, or they do not. Measure is found even in the genus of substances 1 Meta. X, 1, 1052 b 20. • De Virtut. Card., a. 8. 3 I Sent., d. 8, q. 4, a. 2, ad 8. • De Virtut. Card., a. 8. CAN QUALITIES BE MEASURED? 88 where the measure of all other beings in the genus is that substance which has being most perfectly and most simplywho is God.5 Fundamentally, however, measure is said of quantities: that by which the quantity of a thing is made known. The act of measuring is defined in its most general meaning as the act of the intellect applying certain principles to the examination of objects proposed at hand-" to judge or measure is an act of the intellect, applying certain principles to examine propositions." 6 Joining the fundamental quantitative notion of measure to this act of the act of measure, the definition of measure becomes: the act of the intellect applyl.ng...