Reid offers an under-appreciated account of the primary/secondaryquality distinction. He gives sound reasons for rejecting the views of Locke, Boyle, Galileo and others, and presents a better alternative, according to which the distinction is epistemic rather than metaphysical. Primary qualities, for Reid, are qualities whose intrinsic natures can be known through sensation. Secondary qualities, on the other hand, are unknown causes of sensations. Some may object that Reid's view is internally inconsistent, or unacceptably relativistic. However, a (...) deeper understanding shows that it is consistent, and relative only to normal humans. To acquire this deeper understanding, one must also explore the nature of dispositions, Reid's rejection of the theory of ideas, his distinction between sensation and perception, and his distinction between natural and acquired perceptions. (shrink)
Frank Jackson formulated his knowledge argument as an argument for dualism. In this paper I show how the argument can be modified to also establish the irreducibility of the secondary qualities to the properties of physical theory, and ultimately.
Sensibility theorists such as John McDowell have argued that once we appreciate certain similarities between moral values and secondary qualities, a new meta-ethical position might emerge, one that avoids the alleged difficulties with moral intuitionism and non-cognitivism. The aim of this paper is to examine the meta-ethical prospects of this secondary-quality analogy. Of particular concern will be the extent to which McDowell’s comparison of values to secondary qualities supports a viewpoint unique from that of the moral (...) intuitionist. Once we disentangle the various metaphysical and epistemological strands of McDowell’s analogy, McDowell’s position might appear closer to moral intuitionism than initially supposed. This discussion will also help clarify the intended meaning of the secondary-quality analogy, as well as its significance for ethics more generally. (shrink)
: Interpretations of Kant's transcendental idealism have been dominated by two extreme views: phenomenalist and merely epistemic readings. There are serious objections to both of these extremes, and the aim of this paper is to develop a middle ground between the two. In the Prolegomena, Kant suggests that his idealism about appearances can be understood in terms of an analogy with secondary qualities like color. Commentators have rejected this option because they have assumed that the analogy should be read (...) in terms of either a Lockean or a Berkelean account of qualities such as color, and have argued, rightly, that neither can provide the basis for a coherent interpretation of Kant's position. I argue that the account of color that the analogy requires is one within the context of a direct theory of perception, as opposed to Locke's representative account. Using this account of color, the secondaryquality analogy enables us to explain how appearances can be mind-dependent without existing in the mind. (shrink)
Abstract: The 'special composition question' is this: given objects O1, . . . , On, under what conditions is there an object O, such that O1, . . . , On compose O? This paper explores a heterodox answer to this question, one that casts composition as a secondaryquality. According to the approach I want to consider, there is an O that O1, . . . , On compose (roughly) just in case a normal intuiter would, under (...) normal conditions, intuit that there is. (shrink)
Frank Jackson formulated his knowledge argument as an argument for dualism. In this paper I show how the argument can be modified to also establish the irreducibility of the secondary qualities to the properties of physical theory, and ultimately "secondaryquality eliminativism"- the view that the secondary qualities are physically uninstantiated.
In this paper, I argue that Book II, Chapter viii of Locke' Essay is a unified, self-consistent whole, and that the appearance of inconsistency is due largely to anachronistic misreadings and misunderstandings. The key to the distinction between primary and secondary qualities is that the former are, while the latter are not, real properties, i.e., properties that exist in bodies independently of being perceived. Once the distinction is properly understood, it becomes clear that Locke's arguments for it are simple, (...) valid and (in one case) persuasive as well. (shrink)
This book investigates the subjective and objective representations of the world, developing analogies between secondary qualities and indexical thoughts and arguing that subjective representations are ineliminable. Throughout, McGinn brings together historical and contemporary discussions to illuminate old problems in a novel way.
Locke denied that ideas of secondary qualities resemble their causes. It has been suggested that Locke denied this because he accepted a mechanical corpuscular hypothesis about the constitution of objects. This paper shows that this and other usual explanations of Locke's denial are mistaken. Further, it suggests an alternative relationship between the scientific account and Locke's philosophical views, and finally it provides Locke's real justification for his claim that ideas of secondary qualities do not resemble their causes.
Our perceptual systems make information about the world available to our cognitive faculties. We come to think about the colors and shapes of objects because we are built somehow to register the instantiation of these properties around us. Just how we register the presence of properties and come to think about them is one of the central problems with understanding perceptual cognition. Another problem in the philosophy of perception concerns the nature of the properties whose presence we register. Among the (...) perceptible properties are colors and shapes, for example, and there is a long philosophical tradition of drawing and refusing to draw metaphysical distinctions between them. This paper makes a claim about the information-theoretic approach to perceptual cognition in order to argue for a fundamentally epistemological distinction between colors and shapes. What makes shapes and colors seem so different to us is how we carry information about their presence around us. In particular, we can come to know more about the shapes on the basis of perceiving them than we can come to know about the colors. One interesting feature of how this distinction is drawn is that it partially vindicates Locke’s claim that our ideas of primary qualities like shapes resemble them in ways our ideas of colors do not. (shrink)
It seems almost a truism to say that colour is a sensation; and yet Young, by honestly recognizing this elementary truth, established the first consistent theory of colour. So far as I know, Thomas Young was the first who, starting from the well-known fact that there are three primary colours, sought for the explanation of this fact, not in the nature of light, but in the constitution of man. (James Clerk Maxwell, p. 267.)It is doubtless scientific to disregard certain aspects (...) when we work; but to urge that therefore such aspects are not fact, and that what we use without them is an independent real thing-this is barbarous metaphysics. (F. H. Bradley, p. 15.). (shrink)
In this paper we defend the view that the ordinary notions of cause and effect have a direct and essential connection with our ability to intervene in the world as agents.1 This is a well known but rather unpopular philosophical approach to causation, often called the manipulability theory. In the interests of brevity and accuracy, we prefer to call it the agency theory.2 Thus the central thesis of an agency account of causation is something like this: an event A is (...) a cause of a distinct event B just in case bringing about the occurrence of A would be an effective means by which a free agent could bring about the occurrence of B. (shrink)
In this paper we defend the view that the ordinary notions of cause and effect have a direct and essential connection with our ability to intervene in the world as agents.1 This is a well known but rather unpopular philosophical approach to causation, often called the manipulability theory. In the interests of brevity and accuracy, we prefer to call it the agency theory.2 Thus the central thesis of an agency account of causation is something like this: an event A is (...) a cause of a distinct event B just in case bringing about the occurrence of A would be an effective means by which a free agent could bring about the occurrence of B. In our view the unpopularity of the agency approach to causation may be traced to two factors. The first is a failure to appreciate certain distinctive advantages that this approach has over its various rivals. We have drawn attention to some of these advantages elsewhere, and we summarize below. However, the second and more important factor is the influence of a number of stock objections, objections that seem to have persuaded many philosophers that agency accounts face insuperable obstacles. In this paper we want to show that these objections have been vastly overrated. There are four main objections. (shrink)
How are we to define red? We seem to face a dilemma. For it seems that we must define red in terms of looks red. But looks red is semantically complex. We must therefore define looks red in terms of red. Can we avoid this dilemma? Christopher Peacocke thinks we can. He claims that we can define the concept of being red in terms of the concept of being red; the concept of a sensational property of visual experience. Peacocke agrees (...) that his definition of red makes use of a concept that those who possess the concept of being red need not possess; namely, red. But he thinks that this does not matter. For, he says, the definition is justified provided we can specify what it is to possess the concept of being red in terms of the concept of being red. What he tries to show is that this might be so even if no-one could possess the concept of being red unless he possessed the concept of being red. Peacocke has two attempts at showing this. However, both these attempts fail. What Peacocke does show is something weaker. He shows that, using red, we can construct a concept that gives what he calls the constitutive role of the concept of being red; but, importantly, that it gives the constitutive role of red does not suffice for what Peacocke says is required for giving a definition. Thus, if we accept Peacocke's standard for definition, it follows that he gives us no way of avoiding the original dilemma. If this is right then perhaps we should join with those like Colin McGinn who think that we should give up our attempts to define our secondaryquality concepts. (shrink)
The first half of this review article on Locke on primary and secondary qualities leads up to a fairly straightforward reading of what Locke says about the distinction in Essay II.viii, one that, in its general outlines, represents a sympathetic understanding of Locke’s discussion. The second half of the paper turns to consider a few of the ways in which interpreting Locke on primary and secondary qualities has proven more complicated. Here we take up what is sometimes called (...) the Berkeleyan interpretation of Locke (section 6), the understanding of Locke’s resemblance thesis (section 7), and Locke’s views of qualities and their relationship to powers (section 8). (shrink)
Locke’s argument for the primary-secondaryquality distinction is compared with Descartes’s argument (in the Principles of Philosophy) for the distinction between mechanical modifications and sensible qualities. I argue that following Descartes, Locke’s argument for the primary-secondaryquality distinction is an essentially a priori argument, based on our conception of substance, and the constraints on intelligible bodily interaction that this conception of substance sets.
John Locke’s distinction between primary and secondary qualities of objects has meet resistance. In this paper I bypass the traditional critiques of the distinction and instead concentrate on two specific counterexamples to the distinction: Killer yellow and the puzzle of multiple dispositions. One can accommodate these puzzles, I argue, by adopting Thomas Reid’s version of the primary/secondaryquality distinction, where the distinction is founded upon conceptual grounds. The primary/secondaryquality distinction is epistemic rather than metaphysical. (...) A consequence of Reid’s primary/ secondaryquality distinction is that one must deny the original version of Molyneux’s question, while one must affirm an amended version of it. I show that these two answers to Molyneux’s question are not at odds with current empirical research. (shrink)
The Dangerous Book for Boys Abstract: Seventeenth and eighteenth century discussions of the senses are often thought to contain a profound truth: some perceptible properties are secondary qualities, dispositions to produce certain sorts of experiences in perceivers. In particular, colors are secondary qualities: for example, an object is green iff it is disposed to look green to standard perceivers in standard conditions. After rebutting Boghossian and Velleman’s argument that a certain kind of secondaryquality theory is (...) viciously circular, we discuss three main lines of argument for the secondaryquality theory. The first is inspired by an intuitively compelling picture of perception articulated by Reid; the second is that the secondaryquality theory is a conceptual truth; the third line of argument is presented in Johnston’s influential paper ‘How to speak of the colors’. We conclude that all these arguments fail, and that the secondaryquality theory is unmotivated. Keywords: color, secondaryquality, disposition, vision, perception.. (shrink)
Although the importance, both historically and systematically, of the seventeenth century distinction between primary and secondary qualities is commonly recognised, there is no consensus on its exact nature. Apparently, one of the main difficulties in its interpretation is to tell the constitutive from the argumentative elements. In this paper, we focus on the primary-secondaryquality distinctions drawn by Boyle and Locke. We criticise, more specifically, MacIntoshs analysis of them. On the one hand, MacIntosh attributes too many different (...) primary-secondaryquality distinctions to Boyle and Locke. On the other hand, he forbears to attribute a particular primary-secondaryquality distinction to them, which, at least in the case of Boyle, differs genuinely from his main distinction between the mechanical affections of matter and all of matters other qualities. (shrink)
Response-dispositional accounts of value defend a biconditional in which the possession of an evaluative property is said to covary with the disposition to cause a certain response. In contrast, a fitting-attitude account of the same property would claim that it is such as to merit or make fitting that same response. This paper argues that even for secondary qualities, response-dispositional accounts are inadequate; we need to import a normative notion such as appropriateness even into accounts of such descriptive properties (...) as redness. A preliminary conclusion is that the normativity that appears in fitting-attitude accounts of evaluative properties need not have anything to do with the evaluative nature of those properties. It may appear there because evaluative properties—or at least thosefor which fitting-attitude accounts are plausible—really are so much like secondary qualities that it might well be appropriate to think of them as a subclass of secondary qualities. In the second half of the paper I discuss the views of three of the philosophers who have been most influential in discussions of response-featuring accounts of evaluative notions and who explicitly distinguish response-dispositional accounts of value from fittingattitude accounts: John McDowell, Simon Blackburn, and Crispin Wright. I highlight some of the theoretical temptations that can be associated with the assumption that the response-dispositional/fitting-attitude distinction parallels the secondaryquality/evaluative property distinction. (shrink)
Arguably one of the most fundamental phase shifts that occurred in the intellectual history of Western culture involved the ontological reduction of secondary qualities to primary qualities. To say the least, this reduction worked to undermine the foundations undergirding Aristotelian thought in support of a scientific view of the world based strictly on an examination of the real—primary— qualities of things. In this essay, I identify the so-called “Causal Argument” for a reductive view of secondary qualities and seek (...) to deflect this challenge by deriving some plausible consequences that support a non-reductive view of secondary qualities from an Aristotelian view (via the philosophical commentary of Thomas Aquinas). Specifically, my argument has two facets. First, I show that Aristotle’s view both implies recognition of the extramental existence of secondary qualities and is a prima facia natural view to take regarding the ontology of secondary qualities. Second, I show that the Causal Argument, which is thought to undermine a natural view of secondary qualities as real things, loses its bite when one examines perception in light the ontological relationship among the categories of quality, quantity and substance. (shrink)
According to Margaret Wilson, Leibniz is inconsistent when it comes to the question of whether one can have distinct ideas of sensible qualities, and this because he sometimes conceives of sensible qualities as sensations and sometimes conceives of them as complexes of primary qualities. When he conceives of them as sensations, he denies that we can have distinct ideas of sensible qualities; when he conceives of them as complexes of primary qualities, he asserts that we can. In this paper I (...) argue that Wilson is wrong to think that Leibnizian ideas admit of various degrees of confusion or distinctness. I also argue that although Wilson's problem admits of being reformulated in a manner consistent with a correct understanding of Leibnizian perceptions and ideas, this reformulated version of the problem admits to a satisfactory interpretive solution. (shrink)
Physics tells us what is objectively there. It has no place for the colours of things. So colours are not objectively there. Hence, if there is such a thing at all, colour is mind-dependent. This argument forms the background to disputes over whether common sense makes a mistake about colours. It is assumed that..
Secondary and tertiary qualities are plausibly explained along dispositionalist lines. Concepts of such qualities are response-dependent, denoting properties that are partly mind/brain-dependent. Unfortunately, dispositionalism is hard to square with extant versions of naturalistic theories of representation. In particular the standard naturalistic (indicational) semantics of representational content cannot handle the question from either the subjectivist or the dispositional viewpoint. The paper proposes a remedy: the problem can be solved in a smooth and natural way, provided that we revise and supplement (...) the standard semantics in a rather obvious fashion, by allowing the mind/brain-involving properties to figure within it. (shrink)
Demonstrating that in George Berkeley's last major work, Siris, Berkeley had converted to a belief in the usefulness of the concept and existence of minute particles, Moked here posits that Berkeley developed a highly original brand of corpuscularian physics.
In this paper I shall focus attention on a principle which lies at the heart of Locke's distinction between primary and secondary qualities. It is to be found explicitly or implicitly stated at many places in the Essay , but its clearest expression is at E.II.viii.11, where Locke writes that ' Impulse [is] the only way which we can conceive Bodies operate in'. Let us call it 'the impulse principle'. The first task is to describe what exactly the term (...) impulse means here and to what the principle amounts. Next, I shall consider the kind of role the principle plays in the Essay and whether Locke changed his mind about it in the fourth edition. Then, in the main part of the paper, I shall try to show how the impulse principle helps make possible Locke's distinction between primary and secondary qualities. In the course of my discussion I shall refer to some of Locke's pre- Essay writings: the Epitome, the Abr g , his review of Newton's Principia and Draft C.1 It is a subsidiary aim of the paper to show how these writings - particularly the Abr g which ran to over ninety pages of the Biblioth que universelle and was published in 1688 - can be of help in disentangling the main line of argument in Locke's Essay. (shrink)
McDowell, responding to Mackie’s argument from queerness, defended realism about values by analogy to secondary qualities. A certain tension between two interpretations of McDowell’s response is highlighted. According to one, realism about values would indeed be vindicated, but at the cost of failing to provide an appropriate response to Mackie’s argument; whereas according to the other, McDowell does provide an adequate response, but evaluative realism is jeopardized.
The paper presents a novel account of nature and genesis of some philosophical problems, which vindicates a new approach to an arguably central and extensive class of such problems: The paper develops the Wittgensteinian notion of ‘philosophical pictures’ with the help of some notions adapted from metaphor research in cognitive linguistics and from work on unintentional analogical reasoning in cognitive psychology. The paper shows that adherence to such pictures systematically leads to the formulation of unwarranted claims, ill-motivated problems, and pointless (...) theories. To do so, the paper proceeds from a case-study on a lastingly influential development in early modern philosophy: the adoption of the doctrine of secondary qualities, and its principal consequences. The findings motivate a new approach to an arguably extensive and important class of philosophical problems: to the problems we raise in the grip of philosophical pictures. (shrink)
No philosophical intuition has a longer history than that which divides sensible qualities into two kinds, primary and secondary. Something like it appears in Democritus, nearly 2500 years ago, and has been continuously maintained in some form or another ever since then. Philosophers today largely continue to think that there is something right about the distinction, even while it remains notoriously difficult to find agreement on just where its ultimate basis lies. As Mark Johnston (1992) puts it, the primary– (...) class='Hi'>secondary distinction has “the dubious distinction of being better understood in extension rather than intension. Most of us can generate two lists under the two headings, but the principles by which the lists are generated are controversial, even obscure” (229). I hope to shed some light on this obscure question. My thesis, in brief, is that the secondary qualities are those qualities of objects that bear a certain relation to our sensory powers: roughly, they are those qualities that we can readily detect only through a certain distinctive phenomenal experience. Contrary to what is sometimes supposed, there is nothing about the world itself (independent of our minds) that determines the distinction between primary and secondary qualities. Instead, a theory of the secondary qualities must be grounded in facts about how we conceive of these qualities, and ultimately in facts about human perception. (shrink)
QUESTIONS Objects seem to have some properties in themselves (like shape), and some other properties that depend on other things around them (like being alone or accompanied). The distinction between primary and secondary qualities is a special case of this more general contrast: what, according to Locke, is the basis for the distinction? Is there more than one way to understand Locke’s argument: what is the best reading of Locke? What wider signiﬁcance does the distinction between primary and (...) class='Hi'>secondary qualities have? (shrink)
Democritus is generally understood to have anticipated the seventeenthcentury distinction between primary and secondary qualities. I argue that this is not the case, and that instead for Democritus all sensible qualities are conventional.
Several philosophers have argued that "temporal becoming" is mind-dependent, a claim they see as analogous to the traditional one about the mind-dependence of secondary qualities. They have tended to assume that the classical secondary qualities are mind-dependent, and also that the close analogue for time of directly experienced secondary qualities is an irreducibly indexical nowness. In an earlier article it was argued that we should reject the second assumption. Here it is shown why there is indeed a (...) genuine problem of the ontological status of directly experienced temporality and spatiality, a problem analogous to the traditional one about secondary qualities. (shrink)
Descartes and Boyle were the most influential proponents of strict mechanist accounts of the physical world, accounts which carried with them a distinction between primary and secondary (or sensible) qualities. For both, the distinction is a piece of natural philosophy. Nevertheless the distinction is quite differently articulated, and, especially, differently grounded in the two thinkers. For Descartes, reasoned reflection reveals to us that bodies must consist in mere extension and its modifications, and that sensible qualities as we conceive of (...) them based on sense perception can pertain only to the mind. Just how we are supposed to arrive at this realization is, this essay will argue, a deep puzzle that brings us to the basic assumptions of Descartes' metaphysics. For Boyle, by contrast, while reflection can reveal the unique explanatory status of mechanism, and, thus, the primary/secondaryquality distinction, only experience can confirm its truth. Our central focus will be on Descartes, and on the question: How does he intend to remove the sensible qualities from the physical world, how does he strip them from bodies? I will try to show that Descartes has an argument that he takes to show a priori that sensible qualities cannot be attributed to the material world (as foundational qualities, or, as we conceive of them based on sense experience). The argument fails, however, leaving him with at best a partly empirical case for removing the sensible qualities, based on the purported explanatory success of his physics. (shrink)
The understanding of the primary-secondaryquality distinction has shifted focus from the mechanical philosophers’ proposal of primary qualities as explanatorily fundamental to current theorists’ proposal of secondary qualities as metaphysically perceiver dependent. The chapter critically examines this shift and current arguments to uphold the primary-secondaryquality distinction on the basis of the perceiver dependence of color; one focus of the discussion is the role of qualia in these arguments. It then describes and criticizes reasons for (...) characterizing color, smell, taste, sound, and warmth and color as secondary qualities on the basis of our commonsense divisions among sensory modalities; Grice’s proposal for distinguishing among the sensory modalities is focal here. The general conclusion is that reasons for drawing the primary-secondaryquality distinction are unconvincing. (shrink)
For Locke, an idea is ‘the immediate object of perception, thought, or understanding’ (§8).1 Perhaps this is something like a concept: he goes on to give examples of white, cold, and round, which look like they have some representational content. What do these ideas represent? Locke defines a quality: ‘the power to produce any idea in our mind, I call quality of the subject wherein that power is’ (§8). The natural thought is that these ideas represent some (...) class='Hi'>quality of the object, which quality just is the power that the object has to produce that idea in us. Though the idea is in us, the power or quality is clearly in the object. Sometimes, it is true, we speak loosely and refer to the quality of the object by the same name that we use to refer to the idea in us, and talk of white being in the object, for example. Locke cautions that when we speak like this, we should ‘be understood to mean those qualities in the objects which produce them [the ideas] in us’ (§8). (shrink)
Introduction in chapter viii of book ii of An Essay Concerning Human Understanding, John Locke provides various putative lists of primary qualities. Insofar as they have considered the variation across Locke's lists at all, commentators have usually been content simply either to consider a self-consciously abbreviated list (e.g., "Size, Shape, etc.") or a composite list as the list of Lockean primary qualities, truncating such a composite list only by omitting supposedly co-referential terms. Doing the latter with minimal judgment about what (...) terms are co-referential gives us the following list of eleven qualities (in the order in which they appear in this chapter of the Essay): solidity, extension, figure, mobility, motion or rest, number, bulk, texture, motion, size, and situation. Perhaps surprisingly given the attention to the primary/secondary distinction since Locke, Locke's primary qualities themselves have received little more than passing mention in the bulk of the subsequent literature. In particular, no discussion both offers an interpretation of Locke's conception of primary qualities and makes sense of Locke's various lists as lists of primary qualities. A central motivation for this paper is the idea that these two tasks are not independent. (shrink)
Colors aren't as real as shapes. Shapes are full?fledged qualities of things in themselves, independent of how they're perceived and by whom. Colors aren't. Colors are merely qualities of things as they are for us, and the colors of things depend on who is perceiving them. When we take the fully objective view of the world, things keep their shapes, but the colors fall away, revealed as the mere artifacts of our own subjective, parochial perspective on the world that they (...) are. (shrink)
In philosophical discussions of the secondary qualities, color has taken center stage. Smells, tastes, sounds, and feels have been treated, by and large, as mere accessories to colors. We are, as it is said, visual creatures. This, at least, has been the working assumption in the philosophy of perception and in those metaphysical discussions about the nature of the secondary qualities. The result has been a scarcity of work on the “other” secondary qualities. In this paper, I (...) take smells and place them front and center. I ask: What are smells? For many philosophers, the view that colors can be explained in purely physicalistic terms has seemed very appealing. In the case of smells, this kind of nonrelational view has seemed much less appealing. Philosophers have been drawn to versions of relationalism—the view that the nature of smells must be explained (at least in part) in terms of the effects they have on perceivers. In this paper, I consider a contemporary argument for this view. I argue that nonrelationalist views of smell have little to fear from this argument. (shrink)
Philosophical Delusion and its Therapy provides new foundations and methods for the revolutionary project of philosophical therapy pioneered by Ludwig Wittgenstein. The book vindicates this currently much-discussed project by reconstructing the genesis of important philosophical problems: With the help of concepts adapted from cognitive linguistics and cognitive psychology, the book analyses how philosophical reflection is shaped by pictures and metaphors we are not aware of employing and are prone to misapply. Through innovative case-studies on the genesis of classical problems about (...) the mind and perception, and on thinkers including Locke, Berkeley and Ayer, the book demonstrates how such autonomous habits of thought systematically generate unsound intuitions and philosophical delusions, whose clash with reality, or among each other, gives rise to ill-motivated but maddening problems. The book re-examines models of therapeutic philosophy, due to Wittgenstein and J. L. Austin, and develops an approach that may let us overcome philosophical delusions and the problems they engender. In this way, the book explains where and why therapy in called for in philosophy, and develops techniques to carry it out. Introduction : some perplexing discoveries -- Philosophical pictures : the birth of "the mind" -- Through pictures to problems : minds and bodies -- Pictures' effects : from "secondary qualities" to "perceptions" -- The power of pictures : Berkeley's approach -- Self-perpetuating absurdity : Berkeley defends "perceptions" -- Philosophical delusions : Ayer reinvents "perceptions" -- Two turns : a new vision of philosophy -- Linguistic analysis as therapy : Austin on "perceptions" -- Self-reflection as therapy : Wittgenstein on understanding. (shrink)