1. The Mind-Body Problem & What it is like to be a bat

2. Minds and Bodies What is the connection between minds and bodies? Are they made of the same stuff? Three possibilities: 1)Physicalism: everything is physical 2)Dualism: there are two kinds of stuff, physical and mental; or there are two properties of stuff, physical properties and mental properties 3)Idealism: everything is mental

3. Dualism Motivation for dualism: the inexplicability of the mental arising from the physical How can purely physical stuff possibly give rise to our mental life: to consciousness, emotions and intelligence? Doesn’t it seem obvious that our minds are more than our brains? Don’t we have souls? Aren’t we “ghosts in the machine”? Dualism in the west is primarily descended from the Judeo-Christian tradition.

4. Types of dualism 1)Substance dualism There are two types of stuff: mental stuff and physical stuff. Our minds are composed of mental stuff. Everything else in the universe is composed of physical stuff. 2)Property dualism There is only one type of substance, but stuff has two types of properties: mental properties and physical properties.

5. Substance Dualism Rene Descartes (1596-1650 ) The universe contains two types of substance, matter (physical substance) and mind (mental substance). MatterMind Spatially extended not spatially extended Divisibleindivisible Mechanisticindeterministic Does not thinkthinks Dubitableindubitable

6. Descartes “I am a thinking thing” A version of Descartes’s argument: P1I know I am a thinking thing (a mind) P2I do not know that I am a body CTherefore, mind and body are different things. But compare: P1I know Clark Kent is my friend P2I do not know Superman is my friend CTherefore, Clark Kent and Superman are different things

7. A modern argument for dualism David Chalmers Contemporary Australian philosopher b. 1966 The conceivability of zombies – David Chalmers (1996), The Conscious Mind: In Search of a Fundamental Theory

8. A zombie is an imaginary creature that is physically identical to us but which has no conscious mind. It behaves exactly like we do, but has no feelings, no inner life. The claim is that if zombies are conceivable then the physical is distinct from the mental, i.e. dualism is true. Problems: is conceivability enough to prove possibility? Are zombies really conceivable?

9. The interaction problem of dualism If mind and matter are two completely different substances, how can they interact? To affect matter, it would seem that mind must have some physical properties, and vice versa.

10. A solution to the interaction problem? Epiphenomenalism Physical stuff can causally affect mental stuff, but not vice versa. Mental stuff is causally inert. It does nothing in the physical world. Being hit causes pain, but pain does not cause us to yell “ouch”. Pain does not cause us to store memories in physical form. Pain causes nothing. Thoughts cause nothing (or rather our experience of thinking causes nothing). Thoughts as spoken or written have solely physical causes. We are only along for the ride.

11. Property Dualism All substances are physical, but some things have both physical and non-physical (e.g. mental) properties. e.g. brains have emergent non-physical properties e.g. all physical entities also have mental properties (panpsychism)

12. Objections to dualism 1)Intuitive appeal to consistency: why should the world inside our heads be different from everything outside our heads? 2)Interaction problem 3)No evidence 4)Ockham’s razor – In explanations, entities should not be multiplied unnecessarily – i.e. the simplest explanation is generally to be preferred. 5)Lack of explanatory power

13. Idealism Bishop George Berkeley (1685-1753) Everything is mind. Advantages: solves the interaction problem and solves the problem of mere physical things having consciousness, intelligence, etc. Disadvantages: lack of explanatory resources. All explanations appeal to God. Why do things seem physical? Why do things persist? Why do things appear to be explicable through physical laws and reducible to simpler physical objects and forces? Because that’s the way God imagines it.

14. Physicalism Definitions of physicalism Physicalism: the belief that the only kinds of things are physical things and the only kinds of properties are physical properties Physicalism is the belief that everything in the universe can be explained in terms of physics (thus, there is no mysterious non-physical stuff that does not follow physical laws) All mental phenomena can be explained in terms of non- mental phenomena

15. Physicalism with regard to the mind The mind is a biological machine (maybe like a computer). If we understand how the mind works physically, we can understand thoughts, feelings, consciousness A computer or robot could theoretically have a mental life (i.e. consciousness)

16. The Hard Problem of Consciousness

17. Easy and hard problems of consciousness Distinction proposed by David Chalmers The easy problems: finding the neural correlate of consciousness explaining the ability to apply information to thinking and behavior explaining the ability to focus attention, recall items from memory, integrate perceptions, etc. The hard problem: Why does consciousness feel the way it does? Why does it feel like anything?

18. Why the problem is hard “You can look into your mind until you burst, and you will not discover neurons and synapses and all the rest; and you can stare at someone’s brain from dawn till dusk and you will not perceive the consciousness that is so apparent to the person whose brain you are so rudely eye-balling.“ (McGinn 1999) “The problem of consciousness, simply put, is that we cannot understand how a brain, qua gray, granular lump of biological matter, could be the seat of human consciousness, the source or ground of our rich and varied phenomenological lives. How could that ‘lump’ be conscious – or, conversely, how could I, as conscious being, be that lump?” (Akins 1993

19. What is it like to be a bat? Thomas Nagel One of the most famous papers in all of philosophy! (1974) We can never know what it feels like to be a bat.

20. Why a bat? There is something it is like to be a bat. Compare: Cloud, rock, tree – nothing it is to be like Mosquito, frog, computer – who knows? People have different intuitions.

21. Bats are mammals. Most people agree they have experiences – they are conscious. But, their consciousness is alien to us: They “see” by sonar. They fly and hang upside-down. They lust for other bats. We might be able to imagine what it would be like for us to live and behave like a bat. But we can’t imagine what it is like for a bat to be a bat.

22. Problem of subjectivity? Nagel: not a problem of subjectivity e.g. “no one can catch my catches” It’s not that we cannot experience bat token experiences, e.g. Billy the bat’s sonar qualia. Bat qualia are mental types that other subjects could also experience. But we cannot learn what these types are like objectively.

23. Bat’s experience is subjective. Consciousness = having a point of view Scientific knowledge is objective. “The view from nowhere.” Example: lightning – subjective: looks like a flash of light – objective: electrical discharge Study of objective science can never reveal the character of subjective experience.

24. Is this the same as the problem of other minds? Not quite. What is it like to be an eskimo? What is it like to be Tom Cruise? Nagel: we can answer these questions fairly well by using our imagination. But, the answer is accessible to us only because we base our imagination on our own experiences. We need the subjective experience of being human to imagine the experience of others. Objective science alone could not give us these answers. A Martian could not learn from objective facts what it is like to be human.

25. Science cannot explain consciousness in physical terms. “I have not defined the term 'physical'. Obviously it does not apply just to what can be described by the concepts of contemporary physics, since we expect further developments. Some may think there is nothing to prevent mental phenomena from eventually being recognized as physical in their own right. But whatever else may be said of the physical, it has to be objective.” (Nagel 1974) Physical facts are objective. Consciousness is subjective. So consciousness can never be explained by physical facts. Question: Is this right? Are only objective facts physical? Are the objective and the subjective irreconcilable?

26. Is physicalism about mental states wrong? Nagel: not necessarily “It would be a mistake to conclude that physicalism must be false…. It would be truer to say that physicalism is a position we cannot understand because we do not at present have any conception of how it might be true.” (Nagel 1974) Example: we saying “mind is brain” is like pre-Socratic philosopher saying: “matter is energy” “Strangely enough, we may have evidence for the truth of something we cannot really understand.” (Nagel 1974) Example: caterpillar  butterfly