What is an overview of functionalism?
- Thinking of mental properties just in terms of behaviour is too restrictive.
- We can fall more broadly in terms of contribution of mental properties to now the person (or brain) functions; including the interactions of mental properties with each other.
- Such as how one thought leads to another, how desires lead to emotions and vice versa, as well as how any and all of these lead to behaviour.
How does Functionalism define things?
- Think about how you define a knife. You could describe it as a ‘sharp metal object with a handle’ but this would exclude plastic or wooden knives. What’s more important is its function (to cut things).
- Similarly, functionalism says that mental states like pain are determined by their function within the cognitive system.
- For example, the function of pain might be to cause an unpleasant sensation that encourages one to avoid harm.
Is there a problem of multiple realisability?
- No, because when we define things in functional terms they can be anything.
- So pain For example, can be experienced by a human, octopus or alien. Thus functionalism avoids this objection.
What is the challenge of inverted qualia against this theory?
- What if my experience of green was like your experience of blue and vice versa?
- For example, if my qualia when I look at the sea are similar to your qualia when you look at grass.
- When we both look at the sea, our mental states would be functionally identical. They would both, for example, cause us to believe “the sea is blue”.
- And since our mental states are functionally identical, functionalism must say they are the same mental state. But they’re clearly not the same. My qualia are different from yours.
- So the argument is something like:
- If functionalism is true, then two functionally identical mental states are the same mental state
- My mental state when I look at the sea is functionally identical to yours but phenomenally different
- Therefore our two mental states are not the same mental state
- Therefore functionalism is false
What is a summary of Ned Block’s China Brain argument against functionalism?
-Ned Block’s China Brain thought experiment describes a setup that is functionally identical to a mind but is clearly not the same thing.
- These are the key points:
- Imagine we have a complete functional description of human mental states
- A human body is hooked up to the entire population of China
- Every person in China is linked to other people (neurons) via two-way radios
- They communicate according to the rules set out in the complete functional description of human mental states described earlier
- Some of these people (neurons) are linked to the outputs of the body
- Imagine the Chinese population recreated the functions of the neurons
- So, the input leads to exactly the same output, and everything in between is functionally identical
- Basically, the scenario above is designed to replicate a human brain. The population of China is roughly equal to the number of neurons in a brain and the two-way radios replicate the firings of the neurons.
- According to functionalism, the China brain would actually be in pain, say, given the appropriate inputs (like being stabbed). But this is obviously false.
- Just because the example of the China brain is functionally identical to human pain, doesn’t mean the China brain really is in pain. So functionalism is false. There’s clearly more to mental states than their function.
Outline these keywords:
- Direction of Fit.
- Acquaintance knowledge.
- Function.
- Ghost in the machine.
- Qualia.
- Inverted qualia.
- Direction of fit: The direction of the relation between mind and world.
- Acquaintance knowledge: Knowledge if someone or something gained by direct experience (not description) e.g. I know the colour red.
- Function: A mapping from each of the possible inputs to some state of its outputs. The description of a state’s function describes what that state does.
- Ghost in the machine: Ryle’s name for substance dualism.
- Qualia: Phenomenal properties understood as intrinsic and non-intentional properties of mental states.
- Inverted qualia: The thought experiment that supposes they two people experience subjectively different colours when looking at the same object, but otherwise think and behave in identical ways.
What are functional states in terms of inputs and outputs?
- We can give an analysis of mental states in terms of their ‘inputs’ and ‘outputs’.
- Each mental state consists of a disposition to behave in particular ways and have certain other mental states (outputs), given certain inputs from the senses and certain other mental states.
- The complete description of the mental state’s outputs, for each possible set of inputs, is the description of its function. It describes what the mental state does.
- Functionalism claims that mental states just are functional states.
- What it is to be a mental state is just to be a state with certain causal relations to stimuli, behaviour and other mental states.
What are the 2 reasons why functionalism argues that mental states cannot be understood just in terms of behaviour?
- Mental states often cause other mental states. For example, pain normally causes the belief that one is in pain.
- What behaviour a mental state will cause depends on other mental states. So the definition of one mental state will have to mention other mental states.
How does functionalism identify more with physicist theories?
- Functionalism identifies mental states in terms of what they do, not in terms of the nature of the substance that realises those mental states.
- Mental states could be realised by physical states, e.g. of the brain, or they could be realised by states in a distinct mental substance.
- Therefore, Functionalism is logically compatible with both substance dualism and physicalism.
- Paintbrush example. Could be made of cheese.
What is the distinction between causal role functionalists and non-causal role functionalists?
- Causal role functionalism: Functionals should be understood in terms of inputs and outputs.
- A mental state has a particular causal role in causing other mental states, and together with other mental states, in causing behaviour.
- We identify mental states by their causal role.
- Non-Causal role functionalism:
- Whether someone has a particular functional property is just a matter of whether certain hypothetical statements are true about them or not, and whether we can explain and predict their behaviour using such statements.
- No causal chain as it’s hypothetically based.
What is qualia?
- Starts with the idea of phenomenal consciousness.
- Consciousness, especially the sort involved in perception, sensation and emotion has a distinctive ‘experiential quality’.
-It is essentially what is it is like, not a comparison tho like a simile, but it’s supposed to describe how the experience is for the subject.
- We can call the properties of an experience which give it its distinctive experiential quality ‘phenomenal properties’.
- We are aware of these properties through introspection and consciousness, through turning our attention to our conscious experience themselves.
How is qualia different from representational properties and what are these?
- Qualia are non-representational properties, they are intrinsic. These differ to representational properties.
- Representational properties are properties of a mental state that enable it to represent what it does.
- What a mental state represents is what it is ‘about’ e.g. the belief that Paris is the capital of France is about Paris.
- Representational properties, then depend on the way the mental state ‘hooks up’ to the world.
What is the objection of Qualia against functionalism?
-If phenomenal properties are qualia, then they cannot be completely understood in terms of their causal roles (or inputs and outputs on a machine table), because these are relational properties, not intrinsic properties.
P1. Qualia, by definition, are intrinsic, non-intentional properties of conscious mental states.
P2. Intrinsic, non-intentional properties cannot, by definition, be completely analysed in terms of their causal roles (machine table states).
C1. Therefore, if qualia exist, some mental properties cannot be analysed in terms of their causal roles.
P3. Functionalism claims that all mental properties are functional properties which can be completely analysed in terms of their causal roles.
C2. Therefore, if qualia exist, functionalism is false.
P4. Qualia exist.
C3. Therefore, functionalism is false.
-We can challenge P4.
What is the functionalist reply to inverted qualia?
- You and I are not functionally identical.
- There are going to be small, but very important, differences because the causal relations of phenomenal properties are very complex.
- For example, ‘red’ is a warm colour, and ‘green’ is a cool colour.
- To say there is no functional difference between you and me, yet we see colours differently, we have to change a great deal (you have to think of (what I call) green as a warm colour, and so on).
- If we specify the functional role of red enough we will see that whatever is the functional role must be the phenomenal property ‘red’ and can’t be ‘green’.
-It seems like we can conceive of inverted qualia, but in fact, what we have described is impossible.
