Revista de libros teorema Vol. XXXVI/2, 2017, pp. 123-133 Seeing Things As They Are. A Theory of Perception, de JOHN R. SEARLE, NEW YORK, OXFORD UNIVERSITY PRESS, 2015, pp. 235. In his stimulating and provocative book, John Searle challenges two main stances about the nature of visual experience: The Traditional View and Disjunctivism. The former claims that we do not directly perceive external objects, but sense-data – mental objects that represent the external world. The latter argues that we directly perceive the external world; this is so because the external world is part of the visual experience. These two stances support different assumptions concerning the nature of hallucination: The Traditional View argues that perceptual experiences and hallucinations have a mental state in common, when the latter are indistinguishable from the former. From now on, I will call this thesis the Common Factor Principle. Advocates of the Traditional View support this principle arguing that in both cases we perceive sense-data. On the other hand, disjunctivists deny the Common Factor Principle. They claim that both experiences differ in nature, since their intentional contents are different. Whereas in the case of veridical experience the content is an external object, in the hallucinatory bad case the content is a mere appearance of the external object. Searle argues that we directly perceive the external world in the veridical case. However, unlike disjunctivists, he endorses the Common Factor Principle. Searle aims to remove the mistakes of these two stances and to present an alternative view which supports Direct Realism and the Common Factor Principle. For this purpose, Searle criticises an argument supported by The Traditional View dubbed The Bad Argument, which is as follows: visual hallucinations and veridical experiences should receive the same analysis, since they might be phenomenologically indistinguishable. In the hallucinatory case, there is no external object, but there is something that we perceive, namely sense-data. Therefore, we also perceive sense-data in the veridical cases [p. 81]. As a consequence, The Traditional View rejects Direct Realism. Searle points out that the fallacy of the argument lies in mistaking intentional content and intentional object. He argues that we do not perceive intentional contents, but intentional objects, which are objects of the external world. The intentional content is never perceived, because it is itself the seeing of the intentional objects [p. 21]. According to Searle, in a hallucinatory case we perceive nothing because there is no intentional object. However, the subjective experience of a hallucination could be Revista de libros 129 teorema Vol. XXXVI/2, 2017, pp. 123-133 indistinguishable from a veridical experience because both experiences share intentional content. The intentional content determines the phenomenology of the experience, and vice versa. Hence, if both experiences share intentional content, they also share phenomenology. Searle repeats throughout his book that the assumption that we never perceive external objects has brought about many epistemological problems [p. 21]. How can we know facts about the real world on the basis of perception if we never directly perceive the world, but rather we indirectly perceive it through sense-data? In order to solve this problem, the first advocates of The Traditional View – Descartes and Locke – suggested that sense-data resemble material objects. Nevertheless, as Searle mentioned, Berkeley pointed out an objection to this solution: it does not make sense that two entities visually resemble each other, if one of them – the external object – is completely invisible [p. 31]. Although this objection is decisive to refute The Traditional View, the latter survived. However, an alternative view was proposed in the twentieth century – Disjunctivism. As mentioned before, this stance claims that there is no common visual experience that occurs in the veridical and the hallucinatory cases. According to this view, perceptual experience reaches from the brain into the external world. Searle devotes chapter 6 to arguing against Disjunctivism. For this purpose, he presents three objections. (I) There is no way that a subjective experience could be realized in the external object. Searle argues that a subjective experience is a biological phenomenon that takes place in the brain [p. 180]. (II) Disjunctivism fails to give a coherent account of the entities involved in perception. It does not explain how the subjective visual field and the objective visual field are related to each other [p. 198]. (III) Disjunctivism has the same problem as The Traditional View, namely it does not distinguish between the intentional content and the intentional object of the visual experience [p. 173]. Therefore, he claims that this stance is not appropriate to support Direct Realism. Searle develops the alternative to Disjunctivism as follows. He claims that external objects have the essential ability to cause particular subjective experiences. For instance, a red object has the essential ability to 130 Revista de libros teorema Vol. XXXVI/2, 2017, pp. 123-133 cause a particular subjective experience in normal perceivers, namely that of redness. The same experience could be caused by no external object. However, a perceptual experience is satisfied only if the right external object causes the visual experience [p. 37]. Therefore, the intentional content determines the conditions of satisfaction, and these conditions are satisfied if the external object caused the experience. Perceptual experiences, Searle states, are direct presentations of their condition of satisfaction. According to him, this theory is the best way to account for transparency [p. 190]. A perceptual experience is transparent when we give the same description of the perceptual experience that we would give of the state of affairs in the external world. This is one of the most important arguments that disjunctivists use to reject The Traditional View. However, Searle suggests that this is not an argument in favour of Disjunctivism, but against it [p. 190]. This is so because disjunctivists have nothing to offer when it comes to explaining the feature of transparency. How are these two entities – the visual experience and the state of affairs of the external world – related to each other? Searle argues that the visual experience and the state of affairs of the external world are related to each other because the former is an intentional presentation of the latter. But how does Searle think that perceptual experiences get the phenomenal character that they have? He suggests that the subjective visual experience is hierarchical. Complex intentional content, for instance seeing a computer, requires lower-level intentional content, such as seeing colour and shape. Thus, in order to perceive a particular object, it is required to perceive the lower-level perceptual features of that object. These features are settled by the brute facts of our physiology, while the high-level features (external objects) are settled by our epistemology. Therefore, when we see an external object, for instance a computer, we see a computer and we see it as a computer. Both "seeing as" and "seeing that" are contained in perception, but these high-level features are based on the identification of the lowerlevel features [p. 144]. Searle claims that the experience of depth, colour constancy and size constancy are not basic features of perception, but rather intentional high-level features that we acquire as background abilities in order to successfully behave in our environment. Therefore, our perceptual experiences are not only determined by the essential ability that the external object possesses, to cause in us subjective experiences, but they are also determined by our epistemological abilities. As Searle claims, "we have to learn how to see" [p. 70]. Revista de libros 131 teorema Vol. XXXVI/2, 2017, pp. 123-133 After presenting his account in chapters 4 and 5, Searle deals with two well-known issues that concern the nature of perception: the brain in a vat and the spectrum inversion problems. He claims that the point of the brain in a vat thought experiment is to support the Common Factor Principle. Brain processes are sufficient to produce the same kind of visual experience that we have if we perceive the external world. However, in the brain in a vat case, the experience is not satisfied because there is no intentional object that caused that experience. Searle also claims that the spectrum inversion problem is worth considering as a thought experiment. He suggests that if two individuals have different intentional contents, their subjective experience would be different even if their behaviour is the same. Searle suggests, against the Wittgensteinian view about the nature of mental states, that the subjective experience inside our heads is crucial to determine the analysis of mental phenomenon. Many artworks would be ruined if our subjective experiences were different to how they actually are [p. 153]. With all this said, I conclude the analysis of the main theses and arguments of Searle's stance. I have shown the main objections that Searle presents to Disjunctivism, however I felt that Searle's analysis of this account is not accurate enough. He presents Disjunctivism as a simpler and vaguer stance than I think it really is. What follows are some essential points that we should consider to make the most sense of this stance. As Searle mentions, John Campbell – an advocate for Disjunctivism – claims that the three elements of perceptual experiences are the perceiver, the object and the point of view. There is no subjective experience as Searle understands it. As a consequence, Searle claims that Campbell denies the existence of conscious perceptual experiences [p. 192]. Furthermore, he states that Michael Martin and Alva Noë suggest that consciousness goes outside the head and envelops the object itself [p. 180]. Both statements are inaccurate. Searle's misunderstanding lies in that he does not understand the ontological features of visual experience and consciousness as disjunctivists do. According to him, a visual experience is nothing but a subjective mental state inside the head, which emerges from an interaction of neurophysical correlates. Nevertheless, disjunctivists suggest that a visual experience is an event, an interaction between the perceiver and the environment. In my view, claiming that a visual experience is not a subjective experience entirely inside our head does not entail that there is no conscious experience, or that consciousness envelops the external object itself. Like Searle, disjunctivists could support the assumption that consciousness is a biological phenomenon 132 Revista de libros teorema Vol. XXXVI/2, 2017, pp. 123-133 that takes place inside our head. But they might also argue that consciousness is not the perceptual experience itself, but an element of that experience. Another essential element is the external object; therefore, the perceptual experience is an event that occurs not entirely inside our head, since it includes the external object as an element of the experience. Moreover, according to Searle, Campbell claims that the phenomenal character of the visual experience is just the actual physical qualities of the objects [p. 195]. I do not assume that Campbell would support that statement, but rather this one: the phenomenal character of the visual experience is how the physical qualities of the objects are presented to the perceiver from a particular point of view. Note that this is not the same as saying that the phenomenal character is just the physical qualities of the object. Two visual experiences may differ in phenomenology even when the physical qualities are the same, if the environment and points of view vary. Thus, disjunctivists can account for the subjectivity part of the experience, and for cases of visual illusions too. Nevertheless, there is something that all disjunctivists should agree with. As Searle points out, we can support Direct Realism without endorsing Disjunctivism. M. Martin is one of those advocates of Disjunctivism who think that denying the Common Factor Principle is a necessary condition to support Direct Realism [p. 172]. As we have seen, Searle argues that Direct Realism and the Common Factor Principle are compatible. But do we have enough reason to endorse the Common Factor Principle? Searle claims that this principle is not a hypothesis, but a stipulation. He also states that in order to reject this principle, we would have to show that it is logically impossible for a veridical experience and a hallucination to share their phenomenology [p. 168]. I do not see how this would be necessary. There is no empirical evidence or decisive argument for accepting or denying the Common Factor Principle; hence, we should appeal to the method of inference to the best explanation to decide whether we should accept or deny the Common Factor Principle. To conclude, I would like to invite scholars to consider the following alternative. Many psychologists have suggested that hallucinations are degenerate kinds of imagination, that is, vivid mental images which come to mind involuntarily. Thus, hallucinatory cases have phenomenal character, but the phenomenal character of hallucination and the phenomenal character of veridical experiences are of different types. Sometimes, in real cases, both types of experiences are indistinguishable for a particular subject. However, this does not imply that both types of experiRevista de libros 133 teorema Vol. XXXVI/2, 2017, pp. 123-133 ences are the same in nature. The subject may be unable to distinguish between them due to cognitive problems which go further than visual experience. I do not see the incoherence of this stance. So, even though Direct Realism is supported, perceptual and hallucinatory cases could be said to differ in nature. As a consequence, the Common Factor Principle is rejected. All in all, I found Seeing Things as They Are an outstanding book for those who are interested in perception. This book will re-evaluate some of the main assumptions of both The Traditional View and Disjunctivism. It also presents an alternative for those who support Direct Realism and the Common Factor Principle. Raúl Ros Morales Departamento de filosofía Universidad de Murcia Edificio Luis Vives, Campus de Espinardo 30100, Murcia E-Mail: raulros92@hotmail.com