Phenomenology of perceptual illusions.

Abstract

It is perhaps unavoidable that at a certain moment in the evolution of a particular scientific discipline, the terminology may not be very accurate, and the same word can mean different things. This paper aims to contribute to the development of psychological science by focusing on the importance of correct terminology for the progress of scientific theories in the field of visual perception. There are many theories about perceptual illusions. The phenomenological one proposed here is in contrast with those which consider illusions to be errors committed by our perceptual system. As is well known, the role of stimulation in perception is crucial. Hence in the first part of this paper I discuss new ways to interpret sensory stimuli by introducing a new category, that is, second-order stimuli. I examine the relevant relationships between physical stimulation and perception and make their psychophysical nature explicit. In the second part, I inspect the relationships within the appearance world, that is, the phenomenal variables, which are relevant to explaining how the world that we perceive around us is organized. Phenomenological illusions are defined according to the criterion of using only phenomenal variables, those which directly fall within our perception. The key concept of a perceptual illusion is the identity of the perceived object which appears different in different contexts. A series of illusory effects mainly taken from studies on color is examined to describe different kinds of perceptual illusions.

Experimental phenomenology, a challenge.

“…Starting off this special issue, Liliana Albertazzi (2021) contributes an article which delineates the requirements of a theoretical framework for a science of consciousness and, then, discusses the assumptions, objectives, and methods of the phenomenological approach, in contrast to contemporary theories of consciousness. Next, Osvaldo da Pos (2021) contributes an article addressing the role of stimulation in perception and highlighting the principle that illusory characteristics of visual phenomena are independent of the stimulation. Baingio Pinna and Livio Conti (2021) contribute with an original study on incompleteness, as a necessary and sufficient factor for illusory figure formation.…”