Lecture 10: Materialism II The mind-body problem

Today’s Lecture In Today’s Lecture we will: Briefly recap our investigation into the mind-body problem Outline and become introduced to the problem of freedom Examine and discuss the theory of Determinism Outline and critically examine three contemporary approaches to the question of reality Conclude our investigation into the question of reality Today’s Lecture

Recap

So far in phi 100... We are continuing our investigation into the metaphysical question, what is reality? We have considered a number of possible answers: Thales: Reality is composed of water Plato: Reality is composed of two worlds; Being and Becoming Descartes & Locke: Reality is composed of physical and mental substances Berkeley: Reality is composed of ideas or mind We investigated an important consequence of Descartes’ dualism: The mind-body problem And a number of attempts to resolve the problem: Descartes: Tried to find the location in which mind and body interact Ryle: Denies the problem itself is valid Berkeley: Reduced reality to one substance; mind Materialist Monism: Reduces reality to one thing; matter Recap

Recap In our previous lecture we examined the following theories: Materialistic monism The theory that everything is composed of one thing; matter, physical substance etc. Behaviorism Hard Behaviorism: Denies the existence of the mind, mental events, thoughts etc. Soft Behaviorism: Does not deny that the mind may exist but we should limit our investigations to observable, quantifiable behavior. The Mind-Brain identity theory The theory that mental states are identical with brain states Functionalism A theory which attributes minds and mental states to any system that performs functions Recap

The Problem of Freedom

Freedom Mechanistic Materialism Maintained that humans are composed entirely of physical matter All matter is governed by physical, causal laws of nature All human actions are, therefore, governed by causal laws of nature The consequence is that the universe, including everything in it is one big machine Freedom

Newton’s Laws A body remains at rest or in motion with a constant velocity unless acted on by an outside force The sum of the forces acting on a body is equal to the product of its mass and acceleration For every action there is an equal opposite reaction Everything that happens is the result of a prior cause And could not happen other than it did Force Freedom

Freedom The problem of freedom Our problem is this: If humans are entirely composed of matter And all matter is governed by laws of nature Then it follows that human actions are governed by laws of nature Therefore there can be no such thing as freedom or choice Freedom

Freedom Key Questions What do we mean by freedom? Does freedom exist, or is there only necessity? How is freedom possible in a world governed by natural laws? Can we ever know whether there is freedom? If there is freedom, is it an either-or proposition, or are there degrees of it? Do any of these questions matter practically, or are they only of academic interest? What are the consequences if there is no freedom? Freedom

Hard-Determinism

Hard-Determinism Determinism Claims: Every Event Has A Prior Cause Human Actions Are Events Causation and Freedom are incompatible Determinism Must Be True Argues that Causation and Necessity are incompatible with freedom Denies that humans have any choice and that there is no such thing as human freedom Instead; human acts, as events, are all a result of prior necessary causes and therefore not free. Hard-Determinism

There is no necessity or causation influencing the agent’s decision What is freedom? A free action is an action which is free from necessity and causation A free action could have happened other than it did Every time a decision is made there may be a different outcome Choice A Choice B Agent Hard-Determinism There is no necessity or causation influencing the agent’s decision

Hard-Determinism Causation Most Scientific Theories depend on Causal Explanations The relationship between a cause and its effect is often expressed as a law For Example: F=MA; E=MC2 ; XY Scientists maintain that all events are the result of prior causes (A) Event (E) C5 C4 C3 C2 C1 Hard-Determinism

Hard-Determinism Necessity Most scientific theories also assert that if we have a cause (C1) and an event (E1) then E1 will always result from C1 (C1E1) E is a necessary cause of C1. An event (E) could not be other than it was. Event (E) C4 C3 C2 C1 C5 Event (E) C4 C3 C2 C1 C5 Hard-Determinism

Hard Determinism 1 2 3 4 5 Nerves Send Pain Signal to Brain Neurological Processes Pain Behaviour Stepping on Nail All physical events are bound by necessary causal laws Brain processes are physical events Human brains are bound by necessary causal laws Hard Determinism

Hard-Determinism Hard-determinism Experience 1.(a)There Is No Such Thing As Freedom Or Choice (They Are All Illusions) 1.(b) But We Think/Feel That We Do Have Freedom And Choices 2. (a) Every Event (Including Human Actions) Has A Prior, Necessary Cause. 2.(b) All of our science and understanding of the world is based on necessity and causality (2a is true). 3.(b): 1b and 2b Can’t both be true (Either/Or). 3. (a) Freedom And Necessity Are Incompatible Hard-Determinism

Hard-Determinism If determinism is true: Although we may think we have freedom, choices or responsibility; we don’t. They are all illusions! We cannot be held responsible for our actions (whether for reward or punishment) Everything that we have done/are doing/will do was pre-determined before we were even born. Hard-Determinism

Contemporary Approaches

Quantum Physics Quantum Physics Challenges the determinist’s causal model Suggests that the world is not determined so strictly as determinism maintains Distinguishes between the quantum (micro) and macro world In the quantum world: The standard laws of nature do not apply There may be events without causes Not all events are necessary Some scientists even claim that there is no such thing as necessity (or impossibility) Events can only be predicted using statistical probabilities Quantum Physics

Macro Level Quantum Level Quantum Physics

Quantum Physics Problems with quantum physics There is an ongoing investigation into how the quantum world and our world are related How do we go from tiny atoms to objects? Where does the quantum world begin and end? Is the brain determined by quantum or Newtonian laws? It is not clear whether our world is governed by the same laws that apply to the quantum world Billiard balls do not suddenly move without being caused to move Objects do not suddenly vanish or appear into and out of existence We can predict the motions of objects with relative accuracy Objects in our world are stable and solid Quantum Physics

Property Dualism 2. Property Dualism Endorsed by thinkers such as David Chalmers Distinguishes between physical and mental Properties Chalmers maintains: Mental Properties (mental events, minds, thoughts etc.) are real features of the world Any successful theory of reality must include consciousness as a fundamental feature of reality There must be basic laws that relate conscious life to the rest of reality Once these laws are understood the relationship between mind and brain will no longer be a mystery Property Dualism

Property Dualism Implications of Property Dualism If property dualism is correct: Scientists and philosophers need to seek and uncover new laws of nature that explain how conscious life and reality are interrelated Such laws may show that human actions are not strictly determined Criticisms of Property dualism: It is unclear whether these “psychophysical bridging laws” may exist It is also unclear how we might go about finding or investigating such laws Little evidence in support of the existence of such laws Property Dualism

3. Emergence The ‘Principle of Emergence’ maintains that minds are an ‘emergent’ feature of brains Posits the existence of two distinct ‘levels’ in the brain The ‘Supervening’ level emerges as a result of the ‘lower’ level’s physical processes A change at one level effects the other For Example: H20 Cannot be ‘Wet’ or ‘Frozen’ but water (the system) can Humans can be conscious but neurones and synapses cannot be Emergence

Emergence Frozen Water Liquid Water Evaporating Water Supervening Level Lower Level Processes Emergence

Emergence I am hungry I want to eat that candy bar I wonder if Apolo Ohno will win Gold I am thinking about eating turnips Supervening Level Lower Level Processes Emergence

Emergence Implications of theories of emergence If the theory of emergence is correct: Theories of emergence may show that the brain is not as strictly determined as determinists maintain Brains are unique; they are the only things with minds Criticisms of the theory of emergence: It is unclear how the brain generates consciousness We lack a scientific understanding of how such processes may work It is also unclear how we might go about finding or investigating such processes Emergence

The End of Metaphysics

Conclusion Ongoing Perplexities: The scientist maintains that everything has/is/will be explainable using scientific inquiries However there are a number of things the scientist is unable to explain: Human Freedom Human Consciousness The relationship between mind and body The nature and laws that govern the universe and everything in it Conclusion

Conclusion Where do we go from here? Philosophical inquiries can help to show the limits and mistakes inherent in the scientific world-view Some of the things that scientists cannot yet explain may be explained at a later date The inquiry into the question of reality may show that there are some things that scientists are unable to explain There may be some things that can never be explained or understood. Some things may always remain as fundamental mysteries to us To be continued... Conclusion