Naïve realism as a theory of perception is threatened by the issue of hallucinations, as a satisfactory account for this issue is yet to be provided. Naïve realism states that objects are mind independent entities, so through our sense data we perceive the world exactly as it is. Thus, experience fundamentally consists in the subject perceiving the environment, for example, the relationship between the subject looking at an apple is direct and unmediated. The theory faces a number of issues, chiefly, the issue of hallucination, this is as hallucinations seem to express a veridical perception of an ordinary object, however this representation is false as there is no object. Such experiences are “subjectively indistinguishable” (Logue, H. (2012). What should the naïve realist say about total hallucinations?. Philosophical Perspectives) from veridical experiences which is an issue for naïve realists. This essay will discuss the different oppositions to naïve realism given the issue of hallucinations and the attempts made to reconcile the ideas and defend naïve realism.
Firstly, naïve realists attempt to overcome the issue of hallucination by accepting disjunctivism. Disjunctivism rejects the Common Kind Assumption, which argues that whatever experiential event one perceives could occur when hallucinating, this is rejected as veridical perceptual experiences have phenomenal character. According to the naïve realist in good cases, objects “partly constitute one’s conscious experience” (Martin, M. G. F. (1997) “The Reality of Appearances” in M. Sainsbury (ed.) Thought and Ontology Milan: Franco Angeli), if this is true then the mental state of the subject associates with the mind-independent environment, which could not be involved in a hallucinatory situation. Hallucinatory states are therefore a different kind of mental state as there is no sense-data or external object to be related to, thus disjunctivism defends naïve realism. The only common feature of veridical perceptions and hallucinations is that the subject cannot tell using introspection they’re not experiencing veridical perception. However, the screening off argument contests disjunctivism as it argues if hallucination misrepresents the environment as a reality so naïve realism does so no explanatory work. Additionally in the case of hallucination there’s an “elimination” (Logue, What should the naïve realist say about total hallucinations?), of the object so there’s no relation to reality so we cannot identify what it is like to experience a hallucinogenic experience. Exploring the idea further, if veridical experiences and hallucinations are phenomenally indistinguishable, then a whole host more of our perceptual experience could be false and phenomenally indistinguishable. For example, a papier mache rock could appear phenomenally indistinguishable from a real rock, likewise, a hologram of a person could appear phenomenally indistinguishable from a real person. Overall, through incorporating disjunctivism into naïve realism the argument is more persuasive, however, the screening off argument limits its effectiveness.
John L Austin is a defender of naïve realism, he clarifies in his argument that all objects in the material world obey the laws of physics and retain all their properties whether or not anyone is there to observe them. This we all perceive directly and we can objectively identify these features. Thus according to Austin hallucinations are distinct from real perceptions as we are able to identify hallucinations by verifying our experiences with the laws of the material world. Furthermore, Austin argued that as hallucinations are such a rare occurrence we do not need to overly concern ourselves with the issue. David Hume constructed a response to this to claim it is a flawed argument, firstly Hume argues we have a bias blind spot towards ourselves so someone could persuade themselves their hallucinogenic experience fits with the laws of the material world. Furthermore, Hume claims we must accept limits of human knowledge as not all material laws will have been identified yet with human perspectives being kaleidoscopically variable. Overall, Austin’s argument is persuasive and has room for further development such as using multiple point of views to verify veridical experiences, however, Hume’s challenges are valid.
A radical argument against naïve realism is developed by Tim Crane which claims that veridical and hallucinatory accounts of objects are the same, so, in hallucinatory experiences there is no awareness of an object, thus, in veridical experience the subject is not perceptually aware of ordinary objects. Therefore, ‘perceptual experience cannot be what we intuitively think it is’ (Crane, T (2017) “The Problem of Perception”, Metaphysics Research Lab, Stanford University). One potential response to this comes from Mark Kalderon who identifies a causal process linking the organs of perception inside/out of a subjects body with the environment. Causal chains could develop understanding of hallucinations to give them a distinct nature from veridical experience. For causal chains the movement from cause to effect involves intermediate causes that could be bought about even if the initial cause it not there. If perceptual experience is a result of causal processes it is possible to see how hallucinations could come about. Thus, by analysing these causal processes veridical and hallucinatory accounts of objects are distinct by looking at the causes to the effect, disproving Crane’s argument.
Given the issue of hallucinations a number of other theories of perception are arguably more persuasive than naïve realism subsequently. One of these theories is sense data theory (also known as indirect realism). Sense data theory views perception as the relationship between the subject and object mind-dependant, for example, when looking at an apple we are not viewing the apple rather we are viewing a mental image of the apple. Suppose sense-data are the objects of perception in cases of hallucination, it is less problematic as the subject is aware of sense data. However, this approach has other problems as it could lead to radical skepticism as ultimately everything could be a hallucination under the veil of perception – how could we justify the existence of external objects? Another approach that could be favoured over naïve realism is adverbialism which denier that perception is relational to external objects, rather perception is a modification in subjects mind, for example, when seeing a green apple the subject will be seeing greenly and circularly. Thus, perception itself is veridical which avoids naïve realism problems as concerned with the nature of experience. Overall, for many sense data theory and adverbialism could be more convincing than naïve realism as they avoid problems concerning hallucination and nature of experience that naïve realism faces.
Furthermore, naïve realists can account for hallucinations without having to make a other order of existents as sense-data theory has to. Naïve realists have a number of accounts that could be taken, firstly, the state of the brain has immediate awareness in cases of hallucination. Another potential approach is objects of awareness are mental images. Finally, physical space occupants to be the objects of immediate awareness in hallucination. These examples of accounts that naïve realists offer give potential explanations of hallucination without conjuring up a whole other order of existents as with sense data theory.