Charlie Dunbar Broad (18871971) was an English philosopher who for the most part of his life was associated with Trinity College, Cambridge. Broads early interests were in science and mathematics. Despite being successful in these he came to believe that he would never be a first-rate scientist, and turned to philosophy. Broads interests were exceptionally wide-ranging. He devoted his philosophical acuity to the mind-body problem, the nature of perception, memory, introspection, and the unconscious, to the nature of space, time and causation. He also wrote extensively on the philosophy of probability and induction, ethics, the history of philosophy and the philosophy of religion. The ample scope and scale of Broads work is impressive. In addition he nourished an interest in parapsychologya subject he approached with the disinterested curiosity and scrupulous care that is characteristic of his philosophical work.
Broad did not have a philosophyif by that phrase is meant highly original philosophical theories, and a highly original way of approaching philosophical problems. He writes: I have nothing worth calling a system of philosophy of my own, and there is no philosopher of whom I should be willing to reckon myself a faithful follower (1924, p. 77). The reader is nonetheless likely to reap philosophical insights from Broads manner of meticulously setting out and carefully assessing the theories thatprima facieprovide solutions to a given philosophical problem. This feature of his writings is aptly described by A. J. Ayer: The subject is discussed from every angle, the various possibilities judiciously set out, the precedents cited, the fallacious arguments exposed: nothing is skimped: looking for reason, we are not fobbed off with rhetoric (Part of my Life, 1977, pp. 1178). Broad combines fairness, astuteness as well as rare powers of observation.
Philosophers who influenced Broad were (apart from the great philosophers of the past) his teachers at Cambridge, Russell and Moore, and J. M. E. McTaggart and W. E. Johnson; at St. Andrews he received important additional influence from G. F. Stout and A. E. Taylor. The diversity of their thought is mirrored in Broads own exceptional range of interests.
Broad led a relatively uneventful lifenot unlike, he says in his Autobiography, that of a monk in a monastery (1959b, p. 67). He hadnt been out of the British Isles until 1946 when he visited Swedena country he fell in love with, and returned to nearly every year. On a professional level he made acquaintances with several Swedish philosophers (such as Konrad-Marc Wogau at Uppsala University). In the academic year 19534 Broad visited the University of Michigan at Ann Arbor and the University of California at Los Angeles. He writes with great warmth of the kindness and hospitality with which he was received, and adds with characteristic modesty: It was good fun to be treated as a great philosopher (1959b). Broad was a homosexual, and never married.
1. Brief Chronology of Life and Works
2.2 Prehension: the Core Notion of Perceptual Immediacy
2.4 Rivalling Accounts of Perceptual Sensations
2.5 The Theory of Representative Perception
5.3 Broads Knowledge Argument
Primary Literature: Broads Works
1887, born in Harlesden, now a suburb of London, on December 30.
1905, wins a science scholarship to Trinity College, Cambridge.
1911, elected to a fellowship at Trinity; assistant to G. F. Stout, at the University of St. Andrews.
1914, lecturer at Dundee (at the time a part of St. Andrews); during World War I combines lecturing duties with work in a chemical laboratory for the Ministry of Munitions; publication of
1920, elected Professor of Philosophy at the University of Bristol.
1923, Fellow and Lecturer in Moral Science at Cambridge; publication of
1933, Knightbridge Professor of Moral Philosophy at Cambridge; publication of
Examination of McTaggarts Philosophy
Examination of McTaggarts Philosophy
1953, retires from Knightbridge Professorship; publication of
Religion, Philosophy and Psychical Research.
1971, dies age 83 on March 11 in his rooms in Trinity College, Cambridge.
Broad dealt with perception in several works. He is well known as an advocate of The Theory of Representational Realism, according to which our perceptions areindirectcognitive transactions with the world: a perceptual experience of a worldly object is not an immediate awareness of the object itself, but mediated by an immediate awareness of asensum. For example, when we see a coin from a certain angle we are immediately aware of an elliptical sensum.
Broads treatment of perception inThe Mind and Its Place in Naturesets off with a careful description of Nave Realism. And this seems a suitable place to begin our exposition of his theory of perception. What, then, does Nave Realism say? To pre-philosophical reflection perception seem to provide us with some sort of immediate cognitive contact with a physical object, for example a bell. Consider a situation where we perceive a bell. Compare this situation with one where we are merely thinking of a bell. There is a deep difference between the situations. We could vaguely express one part of this difference by saying that in the perceptual situation we are in more immediate touch with the bell than in the thought-situation (1925, p. 144).
This rough and ready picture of the Nave Realist view must, however, be slightly modified. Suppose we visually perceive an apple. Clearly there is a sense in which we do not perceive all of the apple. There is a sense in which we are aware of only apartof its surface; and we are (in that sense) aware only of the sensible colour of that part but not of its sensible temperature. Thus perception provides us with a cognitive contact a part of the apple, but no more. It is, then, strictly speaking only a part of the apple with which we areacquainted; it is only a part of the apple that issensuously manifestedto us. (1925, pp. 14850.)
Broad does not equate or identify the perception of a worldly object with the sort of immediate acquainting awareness we have (or seem to have) with its facing surface (paceChisholm, 1957, p. 154). He is, on the contrary, careful to point out that the experience features more than this awareness: it also has anintentional content. Broad designates this theexternal referenceof the experience. By virtue of its external reference the experience of the apple represents the sensuously manifested constituent as an integral part of a larger spatio-temporal whole, having a whole array of properties not sensuously manifested to us. (1925, pp. 1504.)
What is the nature of the external reference? Broad warns against the risk of unduly intellectualising perception. The external reference is not reached byinferencefrom what is sensuously manifested; nor is it abelieforjudgementsimply accompanying the awareness of the manifested constituent: At the purely perceptual level, people do not have the special experience called belief or judgment (1925, p. 153).
When we visually perceive the apple we have an experience in which its facing red surface is a sensuously manifested objective constituent; we perceive the apple but are, strictly speaking, only acquainted with a portion of it.Broad sometimes prefers to say that weprehendthe facing surface (or ostensibly prehend the surface). Now the notion of prehension is fundamental for an understanding of Nave Realism as well as Representational Realism, so it seems advisable to briefly take a somewhat closer look on Broads account of it.
Broad does not think it is possible to give a strict definition of phrases such as Sprehendsxas red or the equivalent phrase xsensibly presents itself toSas red.What one can do is to contrast the notion of prehension with other notions: The meaning of these phrases cannot be defined, it can only be exemplified. One thing that is certain is that to prehendxas red is utterly different fromjudgingthat it is red orknowingthat it is red (1952a, p. 13; italics in original). For example, in the dark and with my eyes shut I may very well judge (or know) that the apple is red. But in such conditions I am not prehending anything as red, or, what is precisely equivalent, nothing is sensibly presented to me as red (ibid,p. 14). Broad notes that this is substantiated by the fact that a cat or a dog that lacked concepts might, it seems, have a prehension of something as red even though it cannot (lacking the requisite concepts) literally know or judge that it is red.
Prehension is, however, intimately related to knowledge. Broad asks us to consider a subject which has appropriate general concepts and is capable of making judgements and knowing facts. Suppose this subject prehends a certain particular object as red. Then this suffices to enable him toknowthe fact that it is red. Whether he does or does notactuallycontemplate this fact at the time depends on various contingent circumstances (1952a, p. 14; Broads emphasis).
Nave Realism, properly articulated, says that when we perceive a physical object it is only a part of the apple that is sensuously manifested to us: this, and only this, is an objective constituent in the perceptual situation. Now can this view be defended? Broad does not think so. He levels several arguments against Nave Realism, two of which will receive attention here.
TheArgument from Hallucination. Consider a veridical perception and compare it with a subjectively indistinguishable delusive or hallucinatory perception, for example that of a drunkard hallucinating a pink rat. Neither a pink rat nor a part of a pink rat could be a sensuously manifested constituent in the delusive situation.
And, since there is no relevant internal difference between the veridical and the delusive perceptual situation, it is reasonable to suppose that in
case does a perceptual situation contain as a constituent the physical object which corresponds to its epistemological object, even when there is such a physical object. (1925, p. 156; italics added.)
It might be held that the subjective indistinguishability of a veridical perceptual and a hallucinatory situationentailsthat the experiences have an identical constitution (and that, therefore, no material object is a constituent even in the veridical situation). That is, however, not Broads position: itcouldbe that a material objectisan objectively manifested constituent in a veridical situation (whilst not in the indistinguishable hallucinatory situation). He holds, however, that that is not the more reasonable view of the matter.
The Argument from Illusion. Consider a person perceiving a penny from a series of slightly different angles and distances. He would unhesitatingly assume that in each of the slightly differing perceptual situations the facing brownish surface of a certain penny is sensuously manifested to him. But in Broads view this could not be so: If he carefully inspects the objective constituents of these perceptual situations he will certainly find that they seem to be of different shapes and sizes (1925, p. 158). The objective constituent will in most of the situations seemellipticalrather than circular. This indicates, Broad claims, that in each perceptual situation, the constituentthe sensuously manifested itemcannot be the top of the penny. What happens is that instead of being immediately aware of the circular surface of the penny (as he takes himself to be) he is immediately aware of an elliptical item, an elliptical sensum. Hence it is an elliptical sensum rather than the circular surface of the penny that is manifested to the subject. The same holdsmutatis mutandiswhen we perceive a white sheet of paper dimly lit by a candle. On careful consideration it seems clear that the paper looks yellowish to us. So what we are immediately aware of is a yellowish sensum rather than the white sheet of paper we are looking at.
In order to bring out at least some of the facets of Broads theory it seems advisable to turn to a few of the many objections that have been raised against it.
(1) It has sometimes been objected that the argument from illusion is flawed from the start since there is usually no risk of anyone being taken in by the situation. Broads response to this objection is clear. When we look at the penny from an oblique angle it appears elliptical, butnotin the sense that anyone is taking in by the situation, and mistakenly comes to believe or judge that the penny is elliptical. He is explicit on the point: looking elliptical to me stands for a peculiar experience, which, whatever the right analysis of it may be, is not just a mistaken judgement about the shape (1923, p. 237). The pennysensibly appearselliptical. And it is this rather than any supposed tendency to be deceived which creates problem for Nave Realism (paceAustin 1962, p. 26).
(2) It has often been objected that philosophers who have made use of the argument from illusion that they neglect the fact ofperceptual constancy. In his later works Broad admits that this complaint is justified. However, the recognition of the phenomenon of constancy merely shifts the point of application of the argument (1947b, p. 112). There is a class of perceptual experiences of a material object,X, where constancy holds; there is also a class of experiences ofXwhere constancy breaks down. In theory it is logically possible to hold that the facing surface ofXis sensuously presented in the perceptual experiences belonging to the first class but not in the experiences belonging to the second class. But, in view of the continuity between the most normal and the most abnormal cases of seeing, such a doctrine would be utterly implausible and could be defended only by the most desperate special pleading (1952a, p. 9).
What I just said might create the impression that Broads phenomenology is rather unsophisticated or crude. On the whole that is certainly not the case. For example, he points out that the visual field is three-dimensional: A sphere doeslookdifferent from a circle, just as a circle looks different from an ellipse (1923, p. 290; Broads emphasis). And the same holds,mutatis mutandis, for the intimately related characteristics distance and depth; these are also purely visual characteristics of the visual field (pp. 295300).
(The constancy objection to any argument of illusion that appeals to cases such as the penny seen obliquely is a compelling one, to say the least. In spite of that I will, for convenience of exposition, occasionally make use of the example below.)
(3) A stock objection to sense-data theories has been that they invite scepticism with regard to the external world. Broad regrets the sceptical consequences butgiven the strength of the case for the sense-datum theorydoes not consider them sufficient grounds for dismissal. Seeking to preserve as much as possible of the common sense notion of material objects he argues for the existence of such objects conceived of as having primary qualities such as shape, size, and position (apart from such properties as electric charge and mass). (1925, pp. 195204.) Not surprisingly, he rejects the idea that material objects have secondary properties such as (phenomenal) redness or (phenomenal) hotness. Broad is perfectly clear that it does notfollowfrom the fact that such properties are never sensuously manifested in our perceptual experiences that the material objects causing our experiences lack these properties: it does remain possible that there are red and green, hot and cold material objects even though they are not objects of acquaintance. He argues, however, that there is no reason to believe that material objects have these properties. (1925, pp. 2056.)
Now Broad is perfectly clear that the sensum analysis of perception cannot be established simply by pointing to such phenomena as the penny seen obliquely. He does not for a moment suppose that it is possible to logically infer that there is an elliptical sensum from the proposition that something sensibly appears elliptical (paceBarnes 1945, p. 113). What he claims is that there are considerations that can be adduced in support of the sensum analysis. When we look at the penny from the side we certainlyseemto be aware of something elliptical. So we certainly seem to have before our minds something that is elliptical. Obviously we can quite well mistakenlybelievea property to be present which is really absent, when we are dealing with something that is only known to us indirectly, like Julius Csar or the North Pole (1923, p. 241; Broads emphasis). But there are phenomenological differences between perception and belief (or thought) that seem to call for different accounts of their nature. In perception we seem to be dealing with properties that are presented to us. Consider the case of perceiving a stick half immersed in water. Here
we are dealing with a concrete visible object, which is bodily present to our senses; and it is very hard to understand how we could seem to ourselves to
the property of bentness exhibited in a concrete instance, if in fact
was present to our minds that possessed that property. (1923, p. 241; Broads emphasis; see also pp. 2445)
I believe that what Broad is driving at here is that perceptual consciousness has apresentational nature, and it is this that makes it plausible to regard it as involving the literal presence of objects with various qualities, such as colours in the case of visual perception, sounds in auditory, etc.
Broads theory of perception employs an act-object analysis of sensations. Lest it should be thought that he should be incapable to think of any alternative account it should be noted that he examines such an analysis as early as in 1921. G. F. Stout and H. A. Prichard defended such an alternative (both of whom Broad held in the highest regard). Their account could be considered an early version of theadverbial analysisof sensations. Broad asks us to consider a headache. It is by no means clear that a headache means a state of mind with a headachy object [i.e. an act with a certain object]; it seems on the whole more plausible to say that that it is just a headachy state of mind (1921b, p. 392). To have a headache is not to be aware of a headachy object but to feel in a certain way.The alternative account claims that this holdsmutatis mutandisforanytype of sensation. Thus what is described as a sensation of red is a unitary state of mind, and strictly speaking not a state which decomposes into an act of sensing and a sensed red patch.
Broad provides a fairly thorough discussion of the relative merits of the adverbial and the act-object analysis. In a nutshell, his conclusion is that although the adverbial analysis is highly plausible regarding such mental phenomena as bodily feelings; but it is implausible when it comes to those of visual and auditory experiences: the act-object analysis is the more plausible account of such experiences, in Broads opinion. (See Broad 1923, pp. 2527.)
So much for sensations. What aboutsensa? What are they on Broads account? A brief answer must suffice here. Sensa are a certain kind of transitory particulars, which in the case of visual perception have such properties as shape, size, colour, etc (1925, p. 181f.).
The position Broad reaches is the following. A perceptual experience has a certain intentional content. It differs from thought- and belief-episodes by including a sensory phase, and it is primarily this that is responsible for the distinctive phenomenology of perception. The sensory phase consists of sensations. These decompose into acts of sensing and object sensed, sensa. A sensum has the phenomenal properties that the perceived object (sensibly) appears to havered or warm or squeaky. An act of sensing a sensum constitutes an immediate acquainting awareness of the sensum in question. Although our perceptual experiencesseemto grant us an acquaintance with the facing surfaces of material objects, sensa are the only items we are acquainted with.
The intentional contentthe external referenceof a perceptual experience is in a certain sensebased uponsensa (thoughtnotin the sense that there is a train of swift inference leading from the presence of a sensum to the mind to a certain perceptual belief). (1923, pp. 2467.) It is this content which represents the environment as featuring a physical object so-and-so. Sensa are clearly incapable of carrying such content. Furthermore, from the very nature of the case the general notion of physical object cannot have been derived by abstraction from observed instances of it, as the notion of red no doubt has been.In fact, general concept of a physical object is not got out of experience until it has been put into experience. It is best described as an innate principle of interpretation which we apply to the data of sense-perception (1925, p. 217).
It is possible to distinguish roughly three different phases in Broads philosophy of time.
In his (1921a) Broad defends a Russellian theory of time. On thisEternalistview past, present, and future are equally real. There is nothing ontologically special about the present: the present is no more real than the past or the future. Accordingly Broad rejectsPresentismthe view that only the present is realas mere rhetoric rooted in confusion (1921a, p. 226). Presentism has its roots in two errors. One of these errors is to equivocate between two different senses of co-existence. In one sense the parts of any related whole co-exist; in another only those events that occupy the same moment of time co-exist. The whole course of the history obviously cannot co-exist in the latter sense, but this does not prevent it from co-existing in the first. The other error is to believe that past, present, and future are essential characteristics of objects in time in the same way as before and after are, instead of being analysable into the temporal relations of states of mind and their objects (p. 337). Thus Broad rejects the view that past, present, and future are characteristics possessed by objects in time. These characteristics are a mere reflection of our subjective perspective on objects. Some of our mental states are essentially contemporary orsimultaneouswith their objects, e.g. our immediate awareness of sense data. Other states are essentiallylaterthan their objects, e.g. memories. (Cf. p. 336.) A related, and perhaps more important facet of Broads (1921a) position here, is his adoption of a Russellian analysis of tensed discourse. According to this analysisversions of which were later to become orthodoxthe function of tensed verbs or temporal adjectives in tensed statements is performed in the analysans by a tenseless copula, IS, and a temporal relationearlier than,simultaneous with, orlater than. Thus It is raining (or It is raining now) is unpacked as It IS raining at a moment simultaneous with my assertion that it is raining; It has rained (or It rained in the past) is analysed as It IS raining at a moment earlier than my assertion that it has rained; It will rain (or It will rain in the future) is read as It IS raining at a moment later than my assertion that it will rain. (Cf. p. 331.)
InScientific Thought(1923) Broad rejects the Eternalism he had defended in his (1921a) article. He now advances a theory that accepts the reality of the present and the past, but holds that the future is simply nothing at all (1923, p. 66). An all-important corollary of thisGrowing Block Theoryis the thesis thattemporal passageis a fundamental feature of reality. This feature is accounted for in terms of what Broad holds is the most fundamental form of change,becoming. Becoming is the coming into existence of events.
Nothing has happened to the present by becoming past except that fresh slices of existence have been added to the total history of the world. The past is thus as real as the present. On the other hand, the essence of a present event is, not that it precedes future events, but that there is quite literally
to which it has the relation of precedence. The sum total of existence is always increasing, and it is this which gives the time-series a sense [i.e. direction] as well as an order. A moment
includes the sum total of existence
* together with something more. (1923, p. 667; Broads italics.)
An event ispresentby virtue of being the most recent increment of reality; when the event is present there is, as Broad says, nothing to which it stands in the relation of precedence. The eventbecomes pastby virtue of acquiring new relations, and it acquires these relations because the sum total of existence has been increased by the addition of fresh slices of reality. Temporal passage is the continual growth of the sum total of existence.
One of the rivalling views on time Broad discusses is a theory that might be labeledThe Moving Spotlight Theory. The Moving Spotlight Theory accepts the eternalist view that the past, the present, and the future are equally real; it regards the history of the world as existing eternally in a certain order of events. But it differs from the Russellian theory in that it accepts presentness as an irreducible feature of reality. So the fact that the leaf is falling now is not to be analysed as the fact that the event is simultaneous with an utterance or a specific type of mental state. The theory claims that presentness is a characteristic moving along the order of events: Along [the order of events], and in a fixed direction,  the characteristic of presentness [is] moving, somewhat like the spot of light from a policemans bulls-eye traversing the fronts of the houses in a street. What is illuminated is the present, what has been illuminated is the past, and what has not yet been illuminated is the future (1923, p. 59).
Broad is critical of this theory. To understand the nature of time, The Moving Spotlight Theory makes use of a spatial analogy. Such analogies may be useful for some purposes, but it is clear that they explain nothing. Firstly, Broad asks us to consider the successive lighting of presentnessnow on one event and now on another, and so on. This isitselfan event (or a series of events), and ought therefore to be a part of the series of events, and not simply something that happens to the latter from outside (1923, p. 60). If we suppose (as we seem compelled to) that it is not a part of the original series of events, we are launched on a vicious regress of time-dimensions. For then the successive lightning of later events would have to be conceived of as an event of thesecondorderhappening in a time-dimension different from the original one formed by the series of first-order events. Secondly he presents a related line of reasoningsometimes termedThe Rate of Passage Argument: If anything moves, it must move with some determinate velocity. It will always be sensible to ask How fast does it move? But since the series along which presentness is supposed to move is itself temporal, this question becomes: how great a lapse of time 1 does presentness traverse in a unit of time 2? Again, a regress of time-dimensions is imminent. (Both of these arguments receive a clearer formulation and more extensive treatment in Broad (1938).)
Broads later account of time differs in some significant respects from both of the earlier accounts. He now views what he callsabsolute becomingas the rock-bottom peculiarity of time. Absolute becoming manifests itself as the continualsupersessionof what was the latest phase by a new phase, which will in turn be superseded by another new one. This seems to me to be the rock-bottom peculiarity of time, distinguishingtemporal sequencefrom all other instances of one-dimensional order, such as that of points on a line, numbers in order of magnitude, and so on (1959, p. 766).
This theory has, in Broads opinion, various advantages. One advantage mentioned is that it seems to avoid the difficulties with therateof times passagedifficulties which besets the Moving Spotlight Theory, but arguably also the Growing Block Theory. The proposed theory also avoids presupposing that what has not yet supervened and what has already been superseded in some sense co-exist with each other and with what is now occurring, which he views as a defect of the Moving Spotlight Theory. More interestingly, it avoids what Broad now regards as a defect of the Growing Block Theory, viz. that of presupposing that phases, which have already supervened and been superseded, in some sense co-exist with each other and with that which is now happening (1959, p. 767).
(For a book-length study on Broads philosophy of time, see Oaklander 2020.)
Broad discusses the topic of free will in his inaugural lecture Determinism, Indeterminism, and Libertarianism (1934). In this rather dense lecture he approaches the issue by associating free will with moral responsibility. More specifically, he frames it in terms of the conditions necessary and sufficient for the applicability of ought and ought not to actions. Everyone admits, he says, that there is some sense of could in which ought and ought not entail could. The question revolves around the sense of could involved here: in precisely what sense of could is it that if you to ought to perform an action you could perform that action?
Let us introduce a couple of Broads stipulative definitions. An action isobligableif and only if it is an action of which ought to be done or ought not to be done can be predicated. An action issubstitutableif either it was d