P. M. S. Hacker is the leading authority on the philosophy of Wittgenstein. He is author of the four-volume Analytical Commentary on the Philosophical Investigations (1980-96), the first two volumes co-authored with G.P. Baker, and of the epilogue Wittgenstein's Place in Twentieth Century Analytic Philosophy (Blackwell, 1996). He has written extensively on philosophy and neuroscience?Philosophical Foundations of Neuroscience (Blackwell, 2003) and History of Cognitive Neuroscience (Wiley Blackwell, 2008), both co-authored with M.R. Bennett. He has published three volumes of a tetralogy on human nature: Human Nature: The Categorial Framework (Blackwell, 2007), The Intellectual Powers: A Study of Human Nature (Wiley Blackwell, 2013), and The Passions: A Study of Human Nature (Wiley Blackwell, 2018). He is currently completing the final volume ? The Moral Powers: A Study of Human Nature (forthcoming). Together with Joachim Schulte, he has produced the fourth edition and extensively revised translation of Wittgenstein's Philosophical Investigations (Wiley Blackwell, 2009). They are currently working on a new edition and translation of Wittgenstein's On Certainty.

Note to the second edition: Part I: Essays xi

Acknowledgements to the first edition xv

Acknowledgements to the second edition xvii

Introduction to Part I: Essays xxi

Abbreviations xxv

I Introduction to the private language arguments 1

1. The Augustinian conception of language and Wittgenstein's early commitments 1

2. The place of the private language arguments in the Philosophical Investigations 9

3. The Great Tradition and its long shadow 13

4. From grammatical trivialities to metaphysical mysteries 16

5. The dialectic of the mental 21

II Only I can have 25

1. The traditional picture and its predicaments 25

2. Private ownership 28

3. Dispelling conceptual illusions and confusions 33

III Only I can know 41

1. The roots of the problem 41

2. Wittgenstein's response to the classical conception 46

3. Wittgenstein's sketchy account of knowledge 50

4. The cognitive network: connective analysis 54

5. A different route: the functions of the verb 'to know' 57

6. The temptations of the received view resisted 60

7. Further objections rebutted 64

IV Private ostensive definition 69

1. A 'private' language 69

2. Names, ostensive definitions and samples - a reminder 73

3. The vocabulary of a private language 76

4. Idle wheels 85

V Men, minds and machines 89

1. Human beings, their parts and their bodies 89

2. The mind 94

3. Only in the stream of life ... 97

4. Homunculi and brains 100

5. Can machines think? 102

VI Avowals and descriptions 113

1. Descriptions of subjective experience 113

2. Descriptions 115

3. Natural expression 117

4. A spectrum of cases 121

VII Behaviour and behaviourism 127

1. Behaviourism in psychology and philosophy 127

2. Wittgenstein: first reactions 134

3. Cryptöbehaviourism? 142

4. Body and behaviour 146

VIII Knowledge of other minds: the inner and the outer 153

1. Semi¿solipsism 153

2. Inside and outside 155

3. The indeterminacy of the mental 161

IX An overview of the achievement of the private language arguments 167

1. An overview 167

2. Fundamental insights 173

3. Fidelity to philosophical methodology 180

4. Consequences and confusions 185

X Thinking: methodological muddles and categorical confusions 191

1. Thinking: a muddle elevated to a mystery 191

2. Methodological clarifications 194

3. Activities of the mind 196

4. Processes in the mind 202

XI Thinking: the soul of language 207

1. The strategic role of the argument 207

2. The dual¿process conception 212

3. Thought, language and the mastery of linguistic skills 219

4. Making a radical break 225

XII Images and the imagination 229

1. Landmarks 229

2. Seeing, imagining and mental images 236

3. Images and pictures 239

4. Visual images and visual impressions 243

5. Imagination, intention and the will 247

XIII I and my self 251

1. Historical antecedents 251

2. 'The I, the I is what is deeply mysterious' 255

3. The eliminability of the word 'I' 260

4. '"I" does not refer to a person' 264

XIV The world of consciousness 271

1. The world as consciousness 271

2. The gulf between consciousness and body 275

3. The certainty of consciousness 281

XV Criteria 285

1. Symptoms and hypotheses 285

2. Symptoms and criteria 290

3. Further problems about criteria 295

4. Evidence, knowledge and certainty 301

Index 307