A Basis for Judgments of Sensory Intensity

The measurement of sensory intensity has been the subject of much controversy since Fechner proposed his classical formula nearly 100 years ago.1 Some writers have insisted that sensation cannot be measured, holding that measurement is possible only of physical dimensions such as mass, length, and time, or of properties compounded solely of these dimensions. One authority on physical measurement has asserted: ttI know of only one thing clearly outside the range of physics and equally clearly measureable. That is money value.2 Other writers claim that measuring sensation is not essentially different from measuring physical quantities, and, indeed, that ultimate recourse must be made to human sensory judgments for any measurement. Boring has gone so far as to say that if we deny measurement to sensation, we should logically deny it to all physical dimensions as well.3 In an attempt to settle this controversy, the British Association for the Advancement of Science appointed a committee composed of mathematicians, physical scientists, and psychologists, charging this group with instructions to consider and report on the possibility of quantitative estimates of sensory events. After seven years, the committee still found it impossible to agree on an answer to the question under discussion.4 The members could not even define essential terms in a manner acceptable to a11. Certainly, some of the diEculties surrounding this problem would be resolved if we knew the basis of O's responses to questions concerning sensory intensity. Judgments vre obtained with a fair degree of reproduci-