For eight days in 1897, psychologist George Stratton saw the world through a pair of glasses that rotated everything 180 degrees so that up was down and left was right. At first, everything looked upside down and backwards and he stumbled about, crashing into things. By the eighth day, he had largely adapted to the inverting lenses and was able to skillfully maneuver through his environment. Although Stratton's experiment is often cited by psychologists and philosophers of perception, few have effectively addressed the question that interests me most: After adaptation, did the world still look upside-down to Stratton, or at some point did it flip rightside up?
Since after adaptation the upside-down look might no longer seem wrong, in posing this question perhaps I should avoid the word "upside-down", with its implication of error or illusion. So maybe the stays-upside-down view is better expressed as follows. Before donning the inverting lenses, let's suppose, the visual field is toovy when Stratton looks at his room (where "toovy" picks out the phenomenal quality ordinarily associated with its looking like the light is hanging down from above, etc.) and after donning the lenses for the first time, the visual field turns teavy instead (where "teavy" picks out the phenomenal quality ordinarily associated with its looking like the light is jutting up from below). Here are two possibilities for what happens during adaptation: (1.) At some point (perhaps unsteadily and fragmentedly) Stratton's visual experience flips from teavy back to toovy. (2.) Stratton's visual experience stays teavy, but he learns to associate that teavy quality with the light's actually being above him.
These seem like very different phenomenal possibilities. But which is correct? Susan Hurley and Alva Noe (2003) say that things go back to looking toovy -- that post-adaptation, Stratton's visual pheomenology is just the same as it was before donning the glasses (minus the feeling of wearing glasses and other incidentals like the narrowing of the field). They say this partly based upon, and in defense of, a controversial general theory of the relationship between skillful action and conscious experience, and partly based upon James Taylor's 1962 reports in his replication of Stratton. But Taylor's reports, too, are situated within a theoretical framework to which he appears deeply committed, and Stratton's original reports are most naturally interpreted as suggesting the opposite. For example, Stratton writes:
The harmonization of the new experience and the suppression or subordination of insistent remnants of the old were always apparent during active operations in the visual surroundings, as has been described for several of the preceding days. While I sat passively the old localization of unseen parts of my body often came back, or perhaps was the usual form in which they appeared. But the instant I began to rock my chair the new position of these parts came prominently forward, and, except in the case of my shoulders and back, readily felt more real than the old. And in walking, when hands and feet rhythmically made their appearance in the visual field, the old representation, except perhaps for some faint inharmonious sensations in the back, was fully expelled without employing any device of will or of attention whatever (1897c, p. 469).Stratton does not say that the new experience is the same as the old, after adaptation: Rather the new experience is the reverse of the old, and adaptation is the victory of the new in the fight between them.
I don't know which way it goes, but the two possibilities seem to differ, and different observers appear to be giving different reports. The question has implications for the general question of whether skillful action shapes our phenomenology to match the world or whether, instead, phenomenology tends to stay (approximately) the same across the development of skill, only gathering new associations and behavioral contingencies.
I discuss this issue with more everyday examples of mirror reflection in earlier blog posts on the apparent location of mirror images and on the U.S. Department of Transportation's advice that "objects in mirror are closer than they appear".
Similar questions arise, of course, for inverted spectrum cases.