PHILOSOPHY OF MIND AND SCIENTIFIC EVIDENCE

                                              INTRODUCTION

In the early days of my foray into Facebook philosophy groups ‘Philosophy, Science and Utube’ discussion group, which I set up to discuss scientific data and techniques and their relevance to philosophy, had about a hundred members. I had recently joined Analytic Philosophy which also had less than a hundred members, at this time my friend Bill Miessner who is an admin in both groups made a criticism of philosophy. His criticism was that in philosophy you have competing positions with no way of deciding between them, so you just end up arguing in circles. He gave the example of Davidson’s Anomalous Monism which he claimed had no more or less evidence to support it than positions like Identity Theory, or Eliminativism etc. His argument was that it was only really experimental evidence that could resolve these issues so philosophy was not really necessary. Since I think that philosophy and science are continuous I thought it was open to philosophers to use whatever conceptual and scientific resources are available to solve these problems.

            Recently Davidson’s views on Anomalous Monism came up again on Facebook. Eray Oxkural an artificial intelligence researcher claimed that both Davidson and Quine were creationists for arguing for Anomalous Monism. Unfortunately Eray was either unwilling or unable to present his arguments to support his views on Davidson. However, his claims did lead to some interesting discussions on Anomalous Monism. My friend Matt Bush (founder of Analytic Philosophy Facebook Group) argued that Davidson’s Anomalous Monism was false since one of its premises relied on the notion of causation in physics and causation plays no role in modern physics. This set me thinking that if Mat was correct then it would be a nice instance of scientific progress refuting a philosophical position and hence show the importance of using science to make progress in philosophy. It would also support Bill’s claims to some degree.

            However I am not an expert in physics so any conclusions I draw should be taken with a grain of salt, they are meant to draw out discussion and should not be taken to be remotely definitive. A variety of different philosophers have argued that since causation plays no role in our physics then we need to eject it from our fundamental ontology. Russell made this argument in his 1913 paper ‘On the Notion of Cause’ Tim Maudlin made a similar argument in his ‘The Metaphysics Within Physics’ more recently Ladyman and Ross in ‘Everything Must Go’ have made similar arguments. However prior to discussing these arguments I will first outline and discuss Davidson’s argument for Anomalous Monism.

Part 1: Davidson and Anomalous Monism

Davidson builds his argument for Anomalous Monism on three premises:

(1)   Mental Events are causally related to Physical Events.

(2)   Singular Causal relations are backed by Strict Laws.

(3)   There are no strict psychophysical laws.

The above set of premises seem on the face of it to be inconsistent because if mental events are causally related to physical events, and singular causal relations are indeed backed by strict laws then it would seem that contra premise 3 we can indeed have strict psychophysical laws. Davidson argues that contrary to appearances the above premises are consistent and he tried to show why this is the case in his 1970 paper Mental Events.

As an example of a mental event being causally related to a physical event he notes:

“If someone sunk the Bismarck, then various mental events such as perceivings, notings, calculations, judgements, decisions, intentional actions, and changes of belief played a causal role in the sinking of the Bismarck. I would urge that the fact that someone sank the Bismarck entails that he moved his body in ways that was caused by mental events of certain sorts, and his bodily movement in turn caused the Bismarck to sink ” (Davidson: Mental Events p. 208)

So we can see from the above that Davidson is talking about mental events he is referring to intentional actions as opposed to conscious states.  So Davidson’s first premise amounts to the claim that intentional actions causally interact with non-intentional events. He holds that the causal interaction can go the other way. So, for example, a ship driving towards us can cause us to perceive a ship. In this sense Davidson argues that physical events can cause mental events and vice versa.  Given this case one could be forgiven for wondering why he denies that there can be psychophysical laws?

            Firstly he argues that mental events are identical to physical events: by an event, he means an unrepeatable, dated individual e.g. The event of the twin towers being bombed (see Stephen Pinker ‘The Stuff of Thought’ for difficulties in individuating events).  His Anomalous Monism is the position that the mental supervenes on the physical; so mental events depend of physical events, it entails that two events cannot be alike in all physical respects but differ in mental respects, and that an object cannot alter in some mental respect without altering in some physical respect (ibid p. 214). However Davidson argues that despite the proceeding facts this does not mean that we can reduce the psychological to the physical anymore than we can reduce moral properties to descriptive properties. The obvious claim being that morality is prescriptive (normative) and we cannot derive an ought from an is, while intentional descriptions are also irreducibly normative. When we judge that a creature is an intentional system we are attributing a minimal level of rationality to them. We are saying that they can judge that something is the case.  

            There are real weak points to all of Davidson’s premises however I think that premise 3 is the weakest. He argued that there are no psychophysical laws. There is a degree of truth to the claim but this is because when Davidson talks about the psychological he is talking about our standard folk-psychology. Now our folk-psychology like our folk-physics and our folk-biology is the result of our idiosyncratic evolutionary history and our shared cultural heritage. This folk-psychology, folk-physics etc is pragmatically useful but it is also riddled with inconsistencies and is totally ill-equipped to be translated into the language of scientific laws. But as Chomsky correctly argues this doesn’t make the mental anomalous anymore than it makes the physical anomalous, rather it just shows the folly in trying to reduce idiosyncratic folk theories to scientific theories:

“The argument does not seem entirely compelling. For the same reason we should also not compare truisms about balls rolling down hills or a storm brewing in the West with the law of falling bodies, but we are not concerned with the lack of “physico-physical laws”  connecting ordinary discourse about events in the world and explanatory theories of nature…In so far as scientific inquiry might undermine one’s conviction that the Sun is setting or that objects are impenetrable, it seems that it might in principle have similar effects on one’s convictions about the nature of beliefs…Folk Mechanics seems no more susceptible than folk psychology to the formulation of bridge laws. (Chomsky ‘New Horizons in The Study of Language and Mind p. 89)

If Davidson wants us to take his third premise seriously he needs to present us with further arguments on which shows why we should take a lack of psycho-physical laws any more seriously than a lack of physico-physical laws.

            Another objection to Davidson’s premise 3 is that his version of a law relies heavily on a conception of causation that is seriously at odds with anything to be found in science. Davidson gives the following examples of one event causing another:

(1)The eruption of Vesuvius in 79 A.D. caused the destruction of Pompeii.

(2)His lighting the match caused the explosion.

(3)The next California earthquake will cause the destruction of the Golden Gate Bridge.

(4)The hurricane is causing the rise in the water level.

Davidson argues that singular causal statements like the above ones indicate the existence of laws that cover the cases. He then goes on to claim that any justification for the claim that singular causal events are covered by laws will be a-priori. In his explication he notes that singular causal statements are extensional in that their truth value is to remain invariant independent of substitution of co-referring names. So, for example, if (5) ‘Batman caused the Joker to Cry’ is true then (6) ‘Bruce Wayne caused the Joker to Cry’ must be true as well because ‘Batman’ and ‘Bruce Wayne’ refer to the same person. While by a law he means a true universally quantified statement. Strict laws do not admit of ceteris paribus clauses; though less strict laws from the sciences like biology, psychology, etc will have these ceteris paribus clauses.

We have seen already that Davidson argues for his anomalous monism by claiming that intentional statements which are irreducibly normative cannot be reduced to physical statements which form a closed system. So he argues that while mental states supervene on physical states they cannot be reduced to them. (This seems to be connected to the fact that laws in physics are unexceptionable and support counterfactuals whereas laws in the special sciences employ ceteris paribus clauses).

Some people have criticised Davidson by arguing that his premise that true singular causal statements are covered by laws is shown to be false by contemporary quantum physics; in particular the fact that it is not deterministic. Davidson however denies this charge. He argues that laws that he says exist are perfectly compatible with probabilistic laws. This is because such laws are universal and exceptionless (the probabilities they predict have no exceptions) (Davidson: Laws and Cause p. 205). Davidson makes the following point:

“Since it allows probabilistic laws, the cause-law thesis does not (in one fairly standard sense of that messy concept) imply determinism. Neither, then, does it imply complete predictability, even in principle, nor retrodictability.” (ibid p.205)

So we can see that Davidson at least does not see his Law-Cause thesis as being in conflict with quantum mechanics.

                    EVERYTHING MUST GO AND THE NATURE OF CAUSATION

Ladyman and Ross in their (2006) book ‘Everything Must Go’ critiqued analytic metaphysics which relies heavily on our intuitions to construct our metaphysical theory of the world. A lot of their criticisms were directed to philosophers who claim to be naturalistic but who build their metaphysics upon toy models which while intuitively plausible do not correspond with the world revealed by quantum mechanics. This reliance on intuitions they think is a bad thing because our intuitions are not designed to handle really abstract thought about things like quantum mechanics:

“Furthermore, as science progresses we adjust our ontology in accordance with our concern for ontological parsimony. However, practical folk have no systematic reason to be interested in the constraint. Nor could natural selection attend to it when it designed the native anticipatory apparatus used by practical folk. In coping with problems of scarcity, tracking the trajectories through local space and time of bundles of rewards is almost everything. Attention to wider informational dynamics in which processes are embedded typically delivers few if any additional payoffs, and may get in the way of pay off maximization because of computational costs. Therefore modelling causal relations as sequences collisions of objects in time is a sensible heuristic.” (Ladyman and Ross ‘Everything Must Go’ p. 280)”

They are defending Ontic Structural Realism (OSR) which tries to make sense of two conflicting arguments which pull us in different directions about whether we should be realists or anti-realists about science.

(1)The Pessimistic Meta Induction: argues that since science goes through various different revolutions which disregard entities which previous theories were committed to the existence of (e.g. Ether) which supposedly shows that theoretical terms are not actually picking out anything. Arguing inductively people claim that since many revolutions have occurred in the past and unless we assume (implausibly) that our current physics is complete then more revolutions will take place in the future. This shows that we are not justified in believing that our theoretical entities refer to anything. We should rather treat science as an instrumental mode of making accurate predictions: Feynman “Shut Up and Calculate”.

(2) The No Miracles Argument: If our theoretical terms do not pick out mind independent entities then this makes the success of science a miracle. Since there are no miracles in nature then anti-realism must be false. Therefore become a realist fuck head.

These two arguments seem to pull in different directions so OSR tries to solve the problem by saying that it is structure that is preserved across revolutions. A lot of direct reference theories in semantics e.g. Putnam (1975) and Kripke were designed to show how theoretical terms could refer across revolutions. One of the advantages of the direct reference theories is that they could explain reference to theoretical entities within our scientific theories in ways which are more plausible than the descriptivist approach favoured by Frege, Russell and Wittgenstein. Ross and Ladyman seem to think that their OSR can explain theory change in ways that don’t rely on our intuitions in the same way illicit way that Kripke etc do. In chapter 5 of ETMG ‘Causation in a Structural World’ Ladyman, Ross, and Spurret argue that at the level of fundamental physics we should be eliminativists about causation. This argument is accepted would have serious consequences for Davidson’s theory of Anomalous Monism in particular his first two premises which rely heavily on the notion of causation.  

Ladyman et al.  argue that one of the typical explanations of causation in philosophy is done in terms of micro banging of sub-atomic particles.  However since fundamental physics does not justify us in postulating micro banging they claim that we are justified in rejecting explanations which use the unscientific notion of causation. By this they mean that in terms of our most basic ontology which is given to us by contemporary physics causation does not exist. However this fact doesn’t mean that causation cannot play a role in the explanations of the special sciences. They argue that causation in terms of the basic sciences should be thought of as follows:

“It is a concept that structures the notational worlds of observers who must book-keep real patterns from the perspectives that involve temporal and other asymmetries they cannot ignore on pain of discarding information” (ETMG p. 271)

So from the perspective of their scientism when it comes to the special sciences the concept of causation is pragmatically useful in helping us pick out real patterns in our environment. However at the most fundamental level of reality causation does not exist, rather it is what they call a representational real pattern.

            They note that there are two main conceptions of causation one the folk psychological notion and two the scientific conception of causation (and possibly a third notion: causation as explicated by philosophers). We need to be careful when talking about causation to note which version of causation we are eliminating from our fundamental ontology (all versions) and which version we are preserving as a representational real pattern (the scientific conception). One of the primary conceptions of causation is the idea of it as a kind of cosmic glue that holds events together.

            They follow Russell’s views on causation as expressed in his 1913 paper in the sense that they agree that causation finds no role in fundamental physics. However, Russell argued that because causation has no place in fundamental physics it should be eliminated from our ontology altogether. While as we saw above Ladyman et al argue that causation is a real pattern that helps us construct our theories in the special sciences even though it does not play any role in our fundamental physics. So they unlike Russell do not recommend out right elimination of causation.

            As we noted above we need to be careful when trying to analyse the notion of causation and whether it is the folk psychological concept we are talking about or the philosopher’s conception of causation. We know from studies in developmental psychology that as a matter of empirical fact during the normal course of development children do not pick out causal sequences in the same way as Hume believed. People do not need to for two events to be constantly conjoined to believe them to be causally connected. The work of Spelke shows that children from about 4 months have expectations about causation which include the singular causation. Ducasse has shown that students perceive causal patterns based on a single event. Obviously though our pre-theoretic intuitions of causation don’t necessarily tell us about the nature of mind independent reality rather they only tell us about how things seem to us. In fact our intuitions about causality vary depending on the culture we are born into (Cosmides 1989). This fact places serious doubt about whether our intuitions of causation are in any way accurate. From all of this they conclude that our human folk psychology of causation is not Humean, and it is too varied and idiosyncratic to be used as our scientific conception of causality in the special sciences. They follow Patrick Hayes in picking out three core features of folk knowledge (1) It construes causal relations as centred on some agent of change, (2) It postulates various transformative principles (often conceived of as forces) proceeding out from an agent to the recipient of causal influence. (3) It incorporates assumptions about time asymmetry: causal influences flow from the past into the future. (ETMG p. 282)

CAUSES IN SCIENCE:

They begin by criticising Russell who argued that the notion of cause is never used by scientists. They did a corpus analysis of the journal SCIENCE over an 8 year period and found that the term ‘cause’ was used 90 times a month, while the term ‘effect’ was used even more.  They argue that causation as used by scientists is not Humean causation of the simple regularities kind it is actually closer to the folk conception of causation. This they note leaves them with a problem:

 “We have now argued our way into a tight corner. Getting out requires us to seek an account that (i) leaves scientists free to talk about causal processes without risk of embarrassment in the company of metaphysicians, but (ii) follows Russell in denying intuitions (folk or Humean) about causation any role in informing the metaphysical foundations of physics, or science more generally.” (ibid p.289)

Ultimately they reconcile the above seeming contradiction by arguing as follows:

 “So causation, as it figures in science, is a notional-world construct. However, as we argued in 4.5, this notional world provides a useful heuristic for locating some real patterns. It is because special sciences are concerned with relatively isolatable regions of the universe which involve cross-classification from the perspective of less-than-fundamental but nevertheless limiting domains for them, that the causal relationships on which they variously focus will appeal to different aspects of their information-carrying potential”

“We think that Earman and Roberts are correct in their claim that fundamental physics discovers something of a kind that special sciences don’t; and we call this kind of something a universal real pattern. We argued in the preceding sections of this chapter for Russell’s and Redhead’s thesis that these real patterns are not causal. They are instead structural, in the sense articulated in Chapters 2 and 3.” (ibid p.290)

So given their argument and convincing demonstration that causation plays very little role in physics they have cast doubt on Davidson’s first two premises in his argument for Anomalous Monism.

ANOMALOUS MONISM AND THE PRIMACY OF PHYSICS CONSTRAINT

(1)Mental Events are causally related to Physical Events.

(2)Singular Causal relations are backed by Strict Laws.

(3)There are no strict psychophysical laws.

It is important to go through Davidson’s argument in light of Ladyman et al. criticism of the scientific standing of Causation. When Davidson is talking about causal relations between events he is typically referring to macro level events as opposed to events at a microphysical level.  Below are some examples of mental events he discusses in his paper ‘Mental Events’:

(1)The eruption of Vesuvius in 79 A.D. caused the destruction of Pompeii.

(2)His lighting the match caused the explosion.

(3)The next California earthquake will cause the destruction of the Golden Gate Bridge.

(4)The hurricane is causing the rise in the water level.

As can be seen none of the examples are events at the level of fundamental physics. Likewise when he speaks of mental events being causally related to physical events and vice-versa he does not use examples from fundamental physics. So, for example, he talks of mental events like perceiving, believing, planning can cause physical events like the sinking of a ship. None of these examples are anything that Ladyman et al would have a problem with. They would cash out Davidson’s examples of causation as pragmatic constructs which help us navigate the world but which do not obtain at the fundamental level. From the point of view of OSR there should be no problem with premise 1 and saying that mental events like perceiving, intending etc are causally related to physical events like a ship sinking. Premise 2 that singular causal relations are backed by strict laws. Premise 2 amounts to nothing more than a guess. As we have seen above Davidson argues that these causal laws will be extensional, he distinguishes between description of causal laws and the laws themselves. However he has not demonstrated the existence of these causal laws and we have good reasons to think that causation does not obtain at the level of fundamental physics. At the macro-level scientists do indeed appeal to causal laws. However they justify these appeals internal to a theory. As Dennett argues that the intentional stance is justified as follows:

“a pattern exists in some data-is real-if there is a description of the data that is more efficient than the bit map, whether or not anyone can concoct it’ (1991a, 34). Thus there are (presumably) real patterns in lifeless parts of the universe that no actual observer will ever reach, and further real patterns whose data points are before our eyes right now, but which no computer we can instantiate or design will ever marshal the energy to compact.” (Quote taken from Ladyman and Ross)

Now in the case of intentional stance ascription as used by cognitive scientists we have good reasons to think that this requirement is met but we have no real reason to think that it is met at the level of ordinary folk-psychology ascriptions. Davidson never really deals with scientific/computational theories of psychology, all of his descriptions are from folk psychology and there is no good evidence that the generalisations of ordinary folk psychology have strict causal laws. So Davidson gets his third premise for free however it follows trivially from the fact that there is no science of folk-psychology anymore than there is a science of folk-physics (obviously ethno-scientists study the type of folk beliefs that people hold) but we don’t expect folk-physics to be compatible with scientific physics and the same is true of folk psychology. So Davidson’s argument for Anomalous Monism doesn’t really succeed in any meaningful way.