In epistemology and the philosophy of perception, phenomenalism is the view that physical objects do not exist as things in themselves but only as perceptual phenomena or sensory stimuli (e.g. redness, hardness, softness, sweetness, etc.) situated in time and in space. In particular, phenomenalism reduces talk about physical objects in the external world to talk about bundles of sense-data. It has been suggested that this article or section be merged with Knowledge. ... The philosophy of perception concerns how mental processes and symbols depend on the world internal and external to the perceiver. ... A phenomenon (plural: phenomena) is an observable event, especially something special (literally something that can be seen from the Greek word phainomenon = observable). ...

Historical overview

Phenomenalism is a radical form of empiricism and, hence, its roots as an ontological view of the nature of existence can be traced back to George Berkeley and his subjective idealism. As an epistemological theory about the possibility of knowledge of objects in the external world, however, it is probable that the most perspicuous formulation of phenomenalism is to be found in the transcendental aesthetics of Immanuel Kant. According to Kant, space and time, which are the a priori forms and preconditions of all sensory experience, "refer to objects only to the extent that these are considered as phenomena, but do not represent the things in themselves". While Kant insisted that knowledge is limited to phenomena, he never denied or excluded the existence of objects which were not knowable by way of experience, the things in themselves or noumena, though he never proved them. To meet Wikipedias quality standards, this article or section may require cleanup. ... In philosophy, ontology (from the Greek , genitive : of being (part. ... Bishop George Berkeley George Berkeley (British English://; Irish English: //) (12 March 1685 – 14 January 1753), also known as Bishop Berkeley, was an influential Irish philosopher whose primary philosophical achievement is the advancement of what has come to be called subjective idealism, summed up in his dictum, Esse est percipi (To... Subjective idealism is a theory in the philosophy of perception. ... It has been suggested that this article or section be merged with Knowledge. ... Immanuel Kant (22 April 1724 – 12 February 1804), was a German philosopher from Königsberg in East Prussia (now Kaliningrad, Russia). ... Noumena is a melodic death metal band from Finland. ...

Kant's "epistemological phenomenalism", as it has been called, is therefore quite distinct from Berkeley's earlier ontological version. In Berkeley's view, the so-called "things in themselves" do not exist except as subjectively perceived bundles of sensations which are guaranteed consistency and permanence because they are constantly perceived by the mind of God. Hence, while it is true that for Berkeley, objects are merely bundles of sensations (see bundle theory), unlike other bundle theorists, objects do not cease to exist for Berkeley when they are no longer perceived by some merely human subject or mind. Michelangelos depiction of God in the painting Creation of the Sun and Moon in the Sistine Chapel Krishna, the eighth incarnation of Vishnu, one of the manifestations of the ultimate reality or God in Hinduism This article discusses the term God in the context of monotheism and henotheism. ... This article contains information that has not been verified and thus might not be reliable. ...

In the late 19th century, an even more extreme form of phenomenalism was formulated by Ernst Mach, later developed and refined by Russell, Ayer and the logical positivists. Mach rejected the existence of God and also denied that phenomena were data experienced by the mind or consciousness of subjects. Instead, sensory phenomena, for Mach, are "pure data" whose existence is to be considered anterior to any arbitrary distinction between mental and physical categories of phenomena. In this way, it was Mach who formulated the key thesis of phenomenalism and that which separates it from bundle theories of objects: objects are logical constructions out of sense-data or ideas. Ernst Mach Ernst Mach (February 18, 1838 – February 19, 1916) was an Austrian-Czech physicist and philosopher and is the namesake for the Mach number and the optical illusion known as Mach bands. ... Michelangelos depiction of God in the painting Creation of the Sun and Moon in the Sistine Chapel Krishna, the eighth incarnation of Vishnu, one of the manifestations of the ultimate reality or God in Hinduism This article discusses the term God in the context of monotheism and henotheism. ...

Phenomenalism and the bundle theory

Phenomenalism is frequently confused with the bundle theory of perception and vice-versa. According to the bundle theory, objects are made up of sets, or bundles, of ideas or perceptions. To say that the pear before me exists is simply to say that certain properties (greenness, hardness, etc.) are being perceived at this moment. When these characteristics are no longer perceived or experienced by anyone, then the object (pear, in this case) no longer exists. Phenomenalism is the view that objects are logical constructions out of perceptual properties. On this view, to say there is a table in the other room when there is no one in that room to perceive it, is to say that if there were someone in that room, then that person would perceive the table. It is not the actual perception that counts, but the conditional possibility of perceiving.

Phenomenalism of the positivists

The idea of the logical positivists, such as A.J. Ayer and Bertrand Russell, was to formulate the doctrine of phenomenalism in linguistic terms, so as to define references to such entities as physical objects in the external world out of existence. Sentences which contained terms such as "table" were to be translated into sentences which referred exclusively to either actual or possible sensory experiences. Roderick Chisholm definitively refuted this version of phenomenalism in 1948. Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS (18 May 1872 – 2 February 1970), was a British philosopher, logician, and mathematician, working mostly in the 20th century. ... Roderick M. Chisholm Roderick M Chisholm (born in Seekonk, Massachusetts in 1916; died in Providence in 1999) was an American philosopher, known for his work on epistemology, metaphysics, free will, and the philosophy of perception. ...

To see how he did this, note that C.I. Lewis suggested that the physical claim "There is a doorknob in front of me" necessarily entails the sensory counterfactual "If I should seem to see a doorknob and if I should seem to myself to be initiating a grasping motion, then in all probability the sensation of contacting a doorknob should follow." Of course, this statement itself contains references to physical objects which would have to be substituted by sense-data expressions, but the point is clear enough. Chisholm showed that the statement "There is a doorknob..." does not entail the counterfactual statement. If it were to do so, then it must do so without regard to the truth or falsity of any other statement. But suppose the following statement is true: "I am paralyzed from the neck down and experience hallucinations such that I seem to see myself moving toward the door". If this is true, then there could be a doorknob in front of me, I could seem to myself to see a doorknob, and I could seem to myself to be performing the correct sort of grasping motion but with absolutely no chance of having a sensation of contacting the doorknob. Likewise, the statement that "The only book in front of me is red" does not entail the sensory statement "Redness would probably appear to me were I to seem to myself to see a book" because redness is not likely to appear under a blue light-bulb. Clarence Irving Lewis (April 12, 1883 - February 3, 1964) was a pragmatist philosopher. ...

Some have tried to avoid this problem by extending the conditions in the analysandum: instead of "There is a doorknob in front of me" one could have it that "There is a doorknob...and I am not paralyzed, etc.." But if one complicates the analysandum, one must also complicate the analysans. In this particular case, one must analyse in purely sensory terms what it means not to be paralyzed and so on. The same problems would arise with respect to the new analysis and we would have an infinite regress.

Other criticisms

Another common objection to phenomenalism is that in the process of eliminating material objects from language and replacing them with hypothetical propositions about observers and experiences, it seems to commit us to the existence of a new class of ontological object altogether: the sensibilia or sense-data which can exist independently of experience. Indeed, sense-data have been dismissed by some philosophers of mind, such as Donald Davidson, as mythological entities that are more troublesome than the entities that they were intended to replace. John Langshaw Austin (March 28, 1911 – February 8, 1960) was a philosopher of language, who developed much of the current theory of speech acts. ... The concept of sense data (singular: sense datum) is very influential and widely used in the philosophy of perception. ... Donald Davidson (March 6, 1917 – August 30, 2003) was an American philosopher and the Willis S. and Marion Slusser Professor Emeritus of Philosophy at the University of California, Berkeley. ...

A third common objection in the literature is that phenomenalism, in attempting to convert propositions about material objects into hypothetical propositions about sensibilia, postulates the existence of an irreducibly material observer in the antecedent of the conditional. In attempting to overcome this, some phenomenalists suggested that the first observer could be reduced by constructing a second proposition in terms of a second observer, who actually or potentially observes the body of the first observer. A third observer would observe the second and so on. In this manner we would end up with a "Chinese box series of propositions" of ever decreasing material content ascribed to the original observer. But if the not final result is not the complete elimination of the materiality of the first observer (which it cannot be), then the translational reductions that are proposed by phenomalists cannot, even in principle, be carried out.

A final, and perhaps the most devastating objection, to phenomenalism was formulated by R. Firth (1950). The objection stems from perceptual relativity: white wallpaper looks white under white light and red under red light, etc.. Any possible course of experience resulting from a possible course of action will apparently underdetermine our surroundings: it would determine, for example, that there is either white wallpaper under red light or red wallpaper under white light, and so on. On what basis are we to decide which of the hypotheses is the correct one if we are constrained to rely exclusively on sensibilia?

References

• Fenomenismo in L'Enciclopedia Garzanti di Filosofia (eds.) Gianni Vattimo and Gaetano Chiurazzi. Third Edition. Garzanti. Milan, 2004. ISBN 8811505151
• Berlin, Isaiah. The Refutation of Phenomenalism. The Isaiah Berlin Virtual Library. 2004.
• Chisolm, R. "The Problem of Empiricism", The Journal of Philosophy 45 (1948): 512-7.
• C. I. Lewis, An Analysis of Knowledge and Valuation (LaSalle, Illinois: Open Court, 1946), pp. 240, 248-9.
• Bolender, John. Factual Phenomenalism: a Supervenience Theory, in SORITES Issue #09. April 1998. Pp. 16-31.
• Firth, R. "Radical Empiricism and Perceptual Relativity", Philosophical Review. 1950