Definiciones conceptuales

that a person's mental life during sleep is of a very strange kind; it shows that the explanation of his strange behaviour should be given in terms of non- conscious internal mechanisms operative within him rather than in terms of a supposed mental life during sleep.

When Ben Gunn grumbles and mutters about cheeses, let us suppose tiiat he has cheeses on his mind, notwithstanding that he is unaware of events going on around him or even of the fact that he is talking to himself. A silent train of thoughts may cause a person to emit unconscious utterances as if he were expressing or commenting upon his thoughts. Even so, by offering Ben a little piece of Stilton, we should expect him to tell us that that was on his mind. For a person who has recently been thinking certain thoughts is usually able to tell us w hat these thoughts were about, at least if suitably motivated and prompted. And if he cannot remember these things, or appears to remember quite another subject matter, some further or alternative explanation is required.

Sometimes experimental expectations are realised. Suppose, in the first case, that Ben Gunn, aroused by our little piece of Stilton, tells us that it had just crossed his mind that British blue cheese is the best blue cheese. He expresses surprise tliat we should have 'guessed' his thoughts, for he has no memory of having uttered the words we recently heard. In these circumstances, we would conclude that Ben's previous utterances were the expression of thoughts about cheeses which he now remembers. (Let us suppose tliat we can reconcile Ben's remembering something with the supposition tliat he was 'unconscious' by inferring that he remembers his thoughtful expression only under a false description, 'silent soliloquy' or 'words screamed wliilst rimning

from the mad Cheese Eater of Nod'.) Alternative explanations of tlie apparent association could be tested. For example, the hypothesis that Ben is highly suggestible and unwittingly confabulated his 'memory' about Stilton is invited by our hastily designed experimental technique of offering him a little bit cheese. But in the absence of further evidence alternatives to tlie hypothesis tliat Ben remembers his thoughts about cheese have little recommendation. So far, so good. On the assumption that Ben's 'automatic' utterances and subsequent impression are regularly associated in this manner, we may safely infer that Ben remembers thoughts he expressed without being aware tliat he was expressing them.

Experimental expectations are sometimes dashed. Suppose, in a second case, Ben Gunn sincerely professes to remember nothing of cheese. We know that he does not readily forget his recent doings. And our little piece of Stilton was as good a prompt as we can imagine. The behaviour of Gunn is admittedly strange. It defies a satisfactory interpretation in terms of his beliefs and intentions. In some respects it is as if Ben's utterances were tlie expression of beliefs and intentions, in other respects not.

Should we insist that the psychological facts about Ben's thoughts are hidden from view and await to be discovered? I think not. The illusion that there are 'deep' psychological facts behind Ben's strange behaviour stems from the perfectly legitimate desire to discover the inner causes of his behaviour and from tlie fact that we inevitably formulate our general questions about the physiological production of behaviour in psychological terms. We want to know, for example, whether tlie processes which explain Ben's psychologically incoherent behaviour are more like the processes which explain the behaviour of someone who forgets what he intentionally said or more like the processes which explain the production of utterances exhibiting no degree of linguistic

organisation (i.e. incoherent and disjointed babble). We express this question by asking, "Do Ben's utterances as if of cheese non-consciously express thoughts about cheese which he has forgotten or are they meaningless products of a tem porary autom atism ? ". Presum ably, if we knew more about the physiological story - if we knew more about brains and the effects on brams of years of solitude and too much fermented coconut milk - we would find more precise questions to put to Mother Nature. And then it would not bother or surprise us if the evidence gave no decisive answer to our original question.

Ben's behaviour is psychologically unexplained. There are hidden facts to be discovered which will explain his behaviour. But these hidden facts will give a physiological not a psychological explanation. The terms in which tliat explanation will be forthcoming are likely to be very different from tlie terms in which we ordinary South Sea voyagers presently voice our puzzlement about the strange behaviour of Ben Gunn. The psychological question about whether or not Ben really thought about cheeses has its answer. The facts are in view. The answer is no. This <mswer leaves us puzzled. But neither that, nor our unwillingness to admit that Ben Gunn, in the grip of one of liis automatic seizures, is less than 'one of us', should mislead us into supposing that the psycliological question is open to be addressed by the brain sciences.

Experimental expectations are sometimes dashed in the most surprising ways. Suppose, in a third case, that Ben Gunn shows no interest in our little piece of Stilton but speaks earnestly of bacon. Again, we have reason to doubt that his utterance as if of thoughts about cheeses is a non-conscious verbal reaction to thoughts about cheeses which he has forgotten. But now we have a further puzzle, in addition to tlie explanation of his recent talk of cheeses. What is to explain Gun's present talk of hams? The evidence of his recent behaviour points very clearly to the conclusion that he merely appears to

remember thoughts about bacon. We hypothesize that Ben confabulated some story about bacon. But why on earth should Ben confabulate a story about hams? We might say that this is "an autonomic updating of the subject's self­ conception resulting from the sudden re-engagement of his perceptual and kinesthetic processing systems". But, admittedly, this is not so much an explanation as a manner of saying what we already know, namely, that Ben was temporally unaware of his surroundings and behaviour and that he subsequently appeared to remember having thoughts which he did not have.

Our new puzzle about Ben Gunn is tliis: on the one hand it is as if Ben thought about cheeses except that he unaccountably forgot and, on the otlier, it is as if Ben remembers thinking about hams, except Üiat he didn't tiiink about hams. In some respects it is as if Ben expressed thoughts about cheeses and in some respects it is as if he remembered thoughts about hams. We have our answer to tiie question whether Ben non-consciously expressed cheese-tlioughts or whether he remembered bacon-thoughts. Ben did neither of these tilings. Still the puzzlmg phenomena calls out for an explanation.

10, The conclusion that 'sleeptalking’ and 'telling a dream' cannot be explained as the product of a coherent mental life, is consistent with the use of intentional terms to characterise hypotheses about the physiological mechanisms which produce these behaviours.

I have proposed that the explanation of Ben's non-conscious utterances and apparent memories should be sought in discovery of physiological processes which produce this behaviour rather than in discovery of 'hidden facts' about Ben's mental life. How is this overtly Rylean position to be reconciled with tiie activities of cognitive psychologists like Arkin who formulate hypotiieses about the internal mechanisms governing behaviour and characterise these

mechanisms in unashamedly intentional terms? Two conciliatory approaches come to mind. The first proposes that the use of intentional characterisations of neurobiological types is entirely metaphorical. The second approach to reconciliation sees no clear distinction between the literal' use of intentional terms in everyday rationalisations of human action and the 'metaphorical' use of intentional terms in the biological sciences. Instead, it proposes tliat the subject of the intentional characterisations of neurobiological types is not the subject whose behaviour is explained by the interactions of those types witliin him.

Robert Louis Stevenson (1925) drew an analogy between his creative talent for story telling and the remarkable creative talent, sometimes more impressive than his own, evident in the production of his dreams. He attributed the creativity of his dreams to the work of 'little people' working through the night beyond his consciousness or will. The legitimacy of such humuncular explanations in cognitive science has been defended by Demiett (1975). According to Dennett, a clear distinction between personal and sub­ personal levels of intentional explanation is crucial to tlie justification of the use of mental terms in constructing hypotheses about the brain processes which produce behaviour. I am not entirely persuaded by Dennett that the characterisation of inner mechanism in psychological terms should be regarded as anything other than a m etaphor expressing the hypothesis that the physiological process is of a kind frequently associated with the nominal psychological phenomenon. However, I am persuaded tliat Dennett is correct to insist tliat, where inner processes are diaracterised in mental terms, tlie subject of tliese cognitive hypotheses should be distinguished from tlie personal subject of psychology.

Let us suppose that we have observed at lengtli Ben Giuin's periodic states of perceptual detachment associated with non-conscious utterances of varying degrees of linguistic organisation, and have repeatedly aroused and questioned Ben about his recent tlioughts. Among those occasions when Ben's utterances exhibit a fair degree of linguistic organisation we find that (i) sometimes there is an association between Ben's non-conscious utterances and his apparent memories, (ii) sometimes Ben appears to remember nothing, and (iii) sometimes, fairly often in fact, Ben's lengthy non-conscious utterances are succeeded by an equally full apparent memory bearing not the faintest resemblance in its manifest content.

In this third case, it is as if someone had thoughts about cheese and someone else had thoughts about bacon, and neitlier of tliem was Ben. The Cheese Hiinker simultaneously passed his thoughts on to the Publishing Department but failed to get a copy of liis thoughts lodged with the Libraricin. The Ham Thinker was refused immediate publication but stored a copy with the Librarian who supplied it to tlie Editor for publication at a later date. We have a story which attempts to explains how Ben's behaviour was brought about by an organisation of sub-agents within his body. But tliat story does not tell us that Ben intended or was aware of any of tlie internal events which produced his behaviour. Indeed, while part of tlie story attempts to explains how these sub-agents brought about Ben's doing something (his intentional attempt to relate what he recently thought) anotlier part of it attempts to explain behaviour (his non-conscious utterance) of which Ben was not even aware.

We could extend our story to cover cases of type (ii) when Ben appears to remember nothing by supposing that nothing got lodged in the Library and to cover cases of type (i) when there is an association between Ben's non-conscious

utterances and his apparent memories by supposing that the Cheese Thinker both publishes and lodges a copy in the Library. Rival stories might also be told. For example, that the Bacon Thinker didn't work at the same time as tlie Cheese Thinker but tlie Editor mistook his recent output for a library copy. But however attractive or illuminating we find any of these heady tales they should not mislead us into thinking that Ben intentionally expressed thoughts about cheeses or that he genuinely remembers thoughts about bacon or tlioughts about cheese.

'Ben thought about cheeses', however 'natural' a manner of speaking, should be taken harmlessly to imply only tliat Ben Gunn non-consciously uttered certain words tliat in some other circumstances would have been explained by his having cheeses on his mind. Similarly, 'Ben remembered cheeses' or 'Ben remembered hams' should be understood to imply only tliat in some other circumstances Ben's apparent memories would have been explained by his having thought about cheeses or hams and not forgotten w hat he thought. These behavioural similarities, independent of the environm ental and behavioural context which would determine tlieir psychological content, very obviously invite an explanation in terms of common internal processes. The ultimate concern of scientists like Arkin is to construct and test hypotiieses about similarities and distinctions among the internal processes governing behaviour.

11. The phenomenon of Night Terrors has an entirely distinctive physiology