Dehaene begins his discussion of the unconscious with a critique of Freud’s conception of the unconscious. Dehaene notes that despite Freud’s claims to originality in his discovery of the unconscious it was actually discovered years before Freud. Upon hearing this one probably assumes that Dehaene goes on to discuss Schopenhauer and Nietzsche’s work which refers to unconscious emotional drives which unknown to us govern our so called rational conscious behaviour. Schopenhauer’s unconscious ‘will to live’ and Nietzsche’s ‘will to power’  bear a close resemblance to Freud’s unconscious as they involve emotional drives which we are not aware of influencing our conscious behaviour. However, Dehaene doesn’t mention either Schopenhauer or Nietzsche, and he goes on to give an idiosyncratic list of people who discovered unconscious processes, all the while collapsing a lot of important conceptual distinctions.

The unconscious as Freud understood it was intended to refer to unconscious mentalistic processes. Freud didn’t deny that there were bodily processes that we had no knowledge of; and nor did most theorists prior to Freud. Dehaene takes this fact as a kind of refutation of Freud’s originality but the examples that Dehaene gives are examples of non-conscious processes. Thus Dehaene gives the example of Galen noting almost two thousand years ago that our breathing and our ability to walk is not under our conscious control. Now Galen was obviously correct on this point; but it doesn’t really speak to Freud’s concerns. Freud was concerned with unconscious mental states, not with bodily processes which we have no conscious control of. Cell division in the body is not under conscious control but it would be very strange to speak of the body unconsciously dividing cells; rather we would call cell division a non-conscious process. When Dehaene speaks of Hall’s discovery of reflex arcs linking sensory inputs to motor outputs, and our movements originating in our spinal cord (which we have no conscious control over), or Galen’s comments on breathing, he is not showing that Freud was anticipated by these thinkers. Rather Dehaene is merely confusing non-conscious bodily processes with Freud’s mentalistic unconscious. This fact can be seen by the fact that Dehaene even argues that Descartes anticipated Freud in postulating the existence of the unconscious. Descartes is famous in philosophy for denying that unconscious mental states were possible; for Descartes the mind was synonymous with consciousness. Dehaene doesn’t offer much to defend his idiosyncratic interpretation of Descartes; he merely states that Descartes noted that “human actions are driven by a broad array of mechanisms that are inaccessible to introspection, from unconscious motivations to hidden desires” (Consciousness and the Brain p. 51). Dehaene didn’t cite any sources to support his claims about Descartes, which is very strange given the extremely controversial claim he is making. Dehaene is right that Descartes was aware that our body (including the brain) operates according to mechanical principles that we are not aware of. But these non-conscious facts are of an entirely different logical order than the unconscious mental states Freud was concerned with. I am unaware of any textual evidence that Descartes argued for unconscious desires, or motivations of the Freudian kind as Dehaene claimed. I would be interested in any evidence that support’s Dehaene’s claim that Descartes believed in unconscious motivations and desires. But in absence of such evidence I will stick with the standard interpretation of Descartes that he eschewed any talk of unconscious mental processes. Descartes equated consciousness with the ego and the ‘I think’ and argued that it was the conscious mind that controlled the non-conscious body (via the Pineal gland), and not vice versa. So Dehane’s claims about Descartes, Galen et al prefiguring Freud on the issue of the unconscious do not stand up to critical scrutiny.

Dehaene intellectual history doesn’t get it all wrong, he notes that thinkers like Leibniz, Janet, and James to some degree beat Freud to the punch. Leibniz deserves credit for being the first theorist to explicitly argue for unconscious mental processes. This quote from Leibniz in 1704 shows his explicit views on unconscious perception:

“There are hundreds of indications leading us to conclude that at every moment there is in us an infinity of perceptions, unaccompanied by awareness or reflection; that is, of alterations in the soul itself, of which we are unaware because the impressions are either too minute or too numerous, or else too unvarying, so that they are not sufficiently distinctive on their own. But when they are combined with others they do nevertheless have their effect and make themselves felt, at least confusedly within the whole. (Leibniz: New Essays on Human Understanding p. 53)

Leibniz’s unconscious was a mental unconscious and one that prefigured that of Freud by a couple of hundred years, while the non-conscious processes that Descartes, Galen et al discovered had little relation to Freud’s unconscious.

While Dehaene is guilty of confusing unconscious mental states with non-conscious processes such as cell division occurring in the body; it is important to make a further division between the Freudian Unconscious and the Cognitive Unconscious. Both cognitive scientists and psychoanalysts speak of unconscious processes. But in cognitive science the emphasis is less on feelings governing our behaviour that we are not aware of, rather the emphasis is on computational processes that make certain cognitive capacities possible. Thus in areas like perception and language acquisition these capacities are explained interms of computational processes that the brain uses but which we are entirely unconscious of. These computational processes are supposed to be aspects of the mind/brain but we have no conscious awareness of the structure of these cognitive competencies, the structure can only be discovered through detailed scientific research.

There is an ambiguity in how these unconscious cognitive processes are to be interpreted. We saw above that many theorists pre-Freud spoke about non-conscious bodily processes and we discussed how these processes differed from Freud’s mental unconscious. The next question we need to ask is how does the cognitive unconscious relate to the both non-conscious bodily processes and Freud’s mentalistic unconscious?

Given that these unconscious computational processes are supposedly part of our general cognitive structures; then one could argue that despite their different natures the Freudian unconscious is aiming at the same target as the cognitive unconscious, both theories are indirectly describing brain processes. On this view, a possible aim for science could be to integrate cognitive science with the findings of contemporary psychoanalysis. In his 2009 book ‘Freudian Unconscious and Cognitive Neuroscience’ psychoanalyst Vesa Talvite attempts such an integration, and in the process argues that certain tenants of psychoanalysis (in particular the idea of a mentalistic unconscious), will have to be rescinded. Talvite based his conclusion on an argument by philosopher John Searle in his 1992 book ‘The Rediscovery of the Mind’. In that book Searle argued against the existence of the mentalistic unconscious, and Talvite notes that if psychoanalysis is to be integrated with cognitive science then as a result of Searle’s arguments psychoanalysts need to drop the idea of a mentalistic unconscious. What Talvite failed to notice is that Searle’s arguments actually call as much doubt into the existence of the cognitive unconscious as they do on the Freudian unconscious.

In Searle’s 2015 book ‘Seeing Things As They Are’ he has further developed his arguments on the nature of the unconscious. Part of Searle’s reason for discussing unconscious perception is that he thinks that the concept is used to down play the importance of consciousness in our interaction with the world. Searle notes that three phenomena which are sometimes appealed to as a way of undermining the importance of consciousness are (1) Blindsight, (2) Readiness Potential, and (3) Reflexes. Searle notes that while readiness potential and reflexes are very important in making perception possible these processes are not unconscious processes rather they are non-conscious processes like, for example, cell division. He argues that in order for these processes to be counted as conscious they would need to be the type of thing that could be made conscious. Searle makes the following point about unconscious processes:

“There is a level of intentionality, indeed several levels, and there is a level of the neurobiological realisation of the intentionality, indeed, several levels; but there is no psychologically real, but unconscious level of algorithmic processing. The idea is that these mental processes in the intermediate level are supposed to be psychologically real, though totally unconscious. They are not the sort of thing that one could be conscious of, but they provide a scientific explanation of operation of the visual system. No clear sense has been given to the notion that there is any psychological reality to the level of computer implementation…The argument against there being a psychologically real level of the deep unconscious is simply that any intentionality requires aspectual shape…representation is always under some aspect or other. But what is the reality of the aspectual shape when the system is totally unconscious? What is the difference between the unconscious desire for water and the unconscious desire for H2O, both of which may be psychologically real? An Agent might not know that water is H2O, he might mistakenly believe that H2O is something disgusting and want water but not H2O. What fact about him when he is totally unconscious makes him have one desire over the other? ( Searle: ‘Seeing things as they are’ pp. 204-205)

Searle’s argument goes against the grain of both the Freudian unconscious and the Cognitive unconscious he is arguing that both theories are incorrect in postulating deep unconscious processes that cannot be made conscious. Searle thinks that once we see that our perception is made possible by non-conscious processes as opposed to unconscious ones we will see the importance of consciousness. There is nothing psychological about our nonconscious bodily processes, so while they clearly make possible our conscious perceptions they are not in a position to undermine the importance of the conscious act of seeing.

This argument has clear consequences for both cognitive science and psychoanalysis so it needs to be evaluated very closely. Firstly it should be noted that Searle is not denying the existence of unconscious mentality; he has no problem with what Freud would call the subconscious. Something that is subconscious is something that we are not currently conscious of but we can bring to awareness if need be. Thus a person may not be currently thinking of their dogs name but if asked they can access the relevant information. Searle has no problem with this type of unconscious. Where Searle has a difficulty is with supposed unconscious knowledge that we are incapable in principle of accessing. Chomsky has long been a defender of this type of unconscious knowledge:

“There is no reason to suppose that we have any privileged access to the principles that enter into our knowledge and use of language, that determine the form and meaning of sentences or the conditions of their use or that relate the “mental organ” of language to other cognitive systems” (Chomsky: ‘Language and Unconscious Knowledge’ p.244)

Chomsky’s claim that the principles that govern our knowledge and use of language are entirely unconscious is precisely the claim that Searle rejects as simply incoherent.

One of the key problems that Searle has with the picture sketched by people like Chomsky, and Marr is their three sphere explanation of things like vision and language. Marr is generally credited with making this three sphere view explicit in his 1982 book ‘Vision’. In ‘Vision’ Marr noted that there were three levels of explanation (1) The Neurobiological, (2) The Computational, and (3) the psychological.  Searle has no problem with either 1 or 3 but he has serious difficulties with 2; from Searle’s perspective a computational level which is not intentionalistic, nor neurobiological, but is still supposedly mentalistic is incoherent. Searle sees no reason to have any level beyond the neurological and the psychological. This is not merely an argument against the computational theory of the mind it is an argument against unconscious computational processes. Searle thinks that the only real computation is the conscious computation that emerges when a person is actually calculating. So he denies that a computer actually uses computation and he denies that the brains do as well. Searle distinguishes between what he calls intrinsic intentionality and derived intentionality. On Searle’s view humans and other animals are the bearers of intrinsic intentionality, now while it is possible to describe brains, the digestive system, or thermostats as computational devices such descriptions are observer relative (hence non-intrinsic). Searle thinks that describing certain devices as computational may be pragmatically useful but it should be remembered that such devices don’t actually use computation (the computation is in the eye of the observer i.e. the human interpreting the device).

So for Searle, except in the case of creatures with intrinsic intentionality actually doing conscious calculations, there is no computation in the world other than observer relative computation. The obvious question is what does this argument have to do with the unconscious (of either the cognitive or Freudian variety)? Well in the case of the cognitive unconscious the link is pretty obvious. If we consider language acquisition; according to cognitive scientists like Chomsky we acquire our language because of innate computational mechanisms that we use to organise our experiences. These computational mechanisms are unconscious. For Searle while we can describe the brain as using computational mechanisms for certain theoretical purposes this description is observer relative. Take away the scientific observers making these attributions and it makes no sense to say that children’s brains are using computational devices.

Now a critic of Searle could claim that when Searle argues against the idea of unconscious computation this amounts to nothing more than a bizarre decision to use the word ‘computation’ in an idiosyncratic manner. This critic could further argue that attacking the foundations of cognitive science on the basis of a stipulation as to how a word must be used is not very convincing.

Searle however offers more than just an idiosyncratic definition of the word ‘computation’ he also offers an argument as to why computation cannot be unconscious. We will call this argument The Aspectual Argument. Searle asks us to consider the following case: (1) It is claimed that John unconsciously desires Water. (2) Water and H2O pick out the same objects. Therefore (3) If John unconsciously desires Water he Unconsciously desires H20. But (4) John doesn’t know that Water = H20 in fact John thinks that H20 isn’t a pleasant substance but that Water is. Therefore (5) John doesn’t unconsciously desire H20 even though he does unconsciously desire Water. So we can see from the above argument that (3) and (5) contradict each other.

Searle claims that the above is not a problem if we are talking about subconscious knowledge. Thus in the case of subconscious knowledge that can be brought to conscious awareness we can question John. Thus John can discover that he was thirsty through various different behavioural measures; e.g. people pointing out that his is licking his lips, that he appears to be dehydrated, that John keeps looking longingly at a glass of water on the table. Upon this being pointed out to John he agrees that unknown to himself he was thirsty and he can drink the water and to quench the thirst. Now John can be further asked if he knows that Water and H2O referred to the same thing and suppose he replies that no he believed that H20 actually referred to Oil. So based on this simple behavioural procedure we can conclude that while John unconsciously desired water he didn’t unconsciously desire H20. But in terms of the deep unconscious that can never be brought to awareness things are different. If we attribute to John the unconscious desire to drink water and since water refers to H2O we must be attributing to John the unconscious desire to drink H20. Since John is in no position to comment on what he is entirely unconscious of, his explicit claim that he doesn’t believe that H20 and Water are synonymous is not a defeater of the claim about his unconscious desire. And since explicit conscious beliefs are not defeaters of attributions of unconscious knowledge then a claim that John unconsciously desires is water doesn’t distinguish between whether this desire commits John to the unconscious desire for H20.

Readers will of course recognise this form of argument as it has been used by Donald Davidson as a way of casting doubt on attributing beliefs to non-linguistic animals. Davidson argues that when we quantify into belief contexts for linguistic creatures we can run into referential opacity. Thus (1) ‘Superman is the most powerful man in the universe’ is true and Clark Kent = Superman, then (2) ‘Clark Kent is the most powerful man in the universe’ is true as well. However assume that 3 is true: (3) ‘John believes ‘Superman is the most powerful man in the universe’’. Now again Superman = Clark Kent. But that doesn’t make 4 true: (4) ‘John believes ‘Clark Kent is the most powerful man in the universe’. The reason obviously is that John may believe x about Superman and not believe x about Clark Kent because he is unaware that they are the same person.

Davidson noticed a logical problem in the case of attributing beliefs to non-linguistic animals. Attributing beliefs to non-linguistic animals results in different logical behaviour than attributing beliefs to linguistic creatures does. Thus while referential opacity occurs in the linguistic creature case it doesn’t occur in the non-linguistic creature case. So, Davidson asks us to think of a case of a dog chasing a cat up a tree. The dog is barking at the cat. But Davidson notes are we justified in saying (1) The Dog believes ‘the cat is up the tree’, (2) The Dog believes ‘the cat is up the tallest tree in the forest’ (3) The Dog believes ‘The cat is up an Oak etc. Davidson’s point is that we have no evidence to decide what the Dog believes in this case and hence referential opacity that occurs in the case of linguistic believers doesn’t occur when we attribute beliefs to non-linguistic creatures.

Now this is a pretty strong argument for a logical point. Davidson uses this argument to cast serious doubt on whether we are justified in attributing beliefs to animals. Searle uses a similar argument in the unconscious cases with just as dramatic results; the claim that we are not justified in attributing unconscious computational states to people. Interestingly, while Searle uses an argument from referential opacity to argue against unconscious mentality; he has never accepted Davidson’s views animals. In his book ‘Intentionality’ Searle notes:

“…It seems to me obvious that infants and many animals that do not in any ordinary sense have a language or perform speech acts nonetheless have Intentional states. Only someone in the grip of a philosophical theory would deny that small babies can literally be said to want milk and that dogs want to be let out and believe that their master is at the door. There are, incidentally, two reasons to why we find it irresistible to attribute Intentionality to animals even though they do not have a language. First, we can see that the causal basis of the animal’s intentionality is very much like our own, e.g., these are the dog’s eyes, this is his skin, those are his ears, etc. Second we cannot make sense of his behaviour otherwise.” ( Searle: Intentionality p.5)

Searle’s acceptance of the referential opacity argument in the case of unconscious knowledge is at odds with his rejection of it in the case of attributing beliefs to animals. Furthermore the reasons that Searle gives in arguing for animal beliefs are good reasons when applied to the case of unconscious knowledge. So if we attribute to a person an unconscious dislike of their mother we may do so because they behave towards that person in ways consistent with this attitude (though they may consciously deny that this is the case). So this attribution involves similar causal explanations that we use when we attribute a desire/belief to the dog. Likewise unconscious mentalistic explanations are precisely appealed to in cases where otherwise the person’s behaviour is inexplicable. So Searle’s two reasons for attributing beliefs to non-linguistic animals can be used just as easily in the case of unconscious knowledge.

I find neither Searle’s aspectual argument nor the logically similar argument of Davidson very convincing. In both cases we are presented with a scenario where it is not determinate whether an animal believes x or extensionally equivalent alternatives or whether a person unconsciously believes x or extensionally equivalent alternatives. This creates an ambiguity that can affect our interpretations of the subjects understudy. The Davidson/Searle reaction to this ambiguity is to cast a doubt on the psychological reality of the subject understudy. However, a logical argument revealing more ambiguity in our interpretations than expected isn’t sufficient to decide a priori whether non-linguistic animals can have beliefs (Searle of course recognises this). Neither is it sufficient to refute an entire discipline like cognitive science, psychoanalysis and computational neuroscience. I think Searle’s principle that if we have no other theory that can explain the behaviour of a creature than attributing beliefs is an excellent principle and the principle holds in the area of unconscious beliefs.

A nice example of a person seemingly unconsciously thinking is the subject of blind-sight. Searle discussed blind-sight in his recent book ‘Seeing Things as They Are’. He argues that an appeal to blind-sight to undermine the importance of consciousness is not very convincing as blind-sight is such a peripheral aspect of perception. He notes that a person couldn’t drive a car when suffering from blind-sight So, Searle argues that given how limited the effects of blind-sight are there is no reason to think that it undermines the importance of conscious experience in daily life. Now I have no interest in undermining the importance of conscious experience but I think that Searle is here guilty of underestimating the types of blind-sight that exist. Dehaene’s also discusses blind-sight and his discussion Dehaene’s discussion of blind-sight while doing nothing to refute Searle’s claim that blind-sight patients could not drive a car, does paint a more complex picture than Searle’s story. For example Dehaene mentions a patient of psychologist Melvyn Goodale, the patient called D.F suffered from carbon monoxide poisoning and as a result of a lack of oxygen suffered from brain damage in her left and right lateral visual cortexes. As a result of the brain damage D.F. ended up blind when it came to recognising shapes, nonetheless she still maintained some motor control when it came to manipulating shapes. As Dehaene describes her surprising abilities:

“Her motor system always seemed to unconsciously “see” things better than she could consciously. She also adapted the size of her grasp to the objects she reached for- yet she was utterly unable to do so voluntarily, using the finger to thumb distance as a symbolic gesture for perceived size.

       D.F.’s unconscious ability to perform motor actions seemed to vastly exceed her capacity for consciously perceiving the same visual shapes…Although D.F. was unaware of it, information about the size and orientation of objects was still proceeding unconsciously down her occipital and parietal lobes. There, intact circuits extracted visual information about size, location, and even shape that she could not consciously see.” ( Dehaene ‘Consciousness and the Brain’ p. 55)

This ability to perform complex motor activities while not conscious is obviously not at the level of someone with blind-sight driving a car; still the capacities are more complex that Searle’s simple examples indicate. Dehaene even argues that some people with blind-sight are capable of navigating their way through busy corridors (ibid p.55), though he presents no references to verify the truth of this claim. Either way it is clear that blind-sight doesn’t just occur in the simple manner that Searle indicates. Searle just argues that it is obvious that his Dog knows when he is at the door, that his dog is indicating that he is hungry. This argument is a simple inference to the best explanation that Searle has arrived at based on the predictive accuracy of using folk psychological locutions to describe the dogs behaviour. It is pretty obvious that when neuroscientists like Dehaene are trying to explain the behaviour of patients like D.F., by saying she is unconsciously computing information to compute the shape of objects, and they way they should be turned; they are engaging in an inference to best explanation and one that can be modelled in scientifically useful ways. Searle aspectual argument does little to challenge these scientific models.

Overall Searle’s arguments against the Freudian and the Cognitive unconscious are pretty unconvincing. Searle himself doesn’t accept similar arguments when applied towards attributions of knowledge to babies or dogs. Searle uses inference to the best explanation arguments when attributing intentional states to dogs and non-linguistic babies; so there is little reason why he should ban similar inferences to the best explanations in the case of positing unconscious mental states.

So psychoanalysts like Talvite need not worry about Searle’s a-priori argument having demonstrated that the mentalistic unconscious in incoherent. Searle’s argument neither refutes the psychoanalytic unconscious, nor does it refute the Freudian Unconscious. Whether a bridge can be found between psychoanalysis and cognitive science is a different question; and is beyond the remit of this paper. What is certain is that if such projects are to be tried greater care is needed than was given by Dehaene in his caricature of Freud.