Roberts, F.S. (1993). Time-perception and precognition: A resolution of the intervention paradox. JSPR, 59, 141-148.
Reproduced with the kind permission of Peter Roberts.
List of papers by the author; archived at

Time-perception and precognition: A resolution of the intervention paradox

by F. Sommerville Roberts

An assessment of time appreciation suggests that it is a manifestation of perception with characteristics similar to visual perception. Based on these observations, a hypothesis is put forward to explain the different aspects of precognition.

One of the more baffling aspects of parapsychology is the phenomenon of precognition. The literature in the Society's archives, and many books on the subject, contain innumerable well-authenticated accounts of precognitive dreams and experiences, which would normally be regarded as sufficient anecdotal evidence to justify acceptance of this phenomenon. However, there is one apparently insurmountable objection to such a step : if someone, say, has a dream that on a certain day in the future he will fall overboard from a boat, and as a result decides to stay at home on that day, then the precognized event does not take place and the dream cannot be a precognitive experience. One cannot have foreknowledge of a non-existent event. This is the classic objection to all forms of prophecy and for centuries has been regarded as an immovable objection to any form of knowledge of the future. Work on the subject has therefore been limited almost entirely to recording alleged experiences. However, there is a flaw in this argument and, once this is recognized, precognition has to be viewed in a different perspective.

It is not necessary to have a discourse on the nature of time, provided some characteristics of the orthodox conception of time are accepted. Time has length, or extension —we can have a long time or a short time —and we can divide it into the past and the future. We cannot observe anything in either the past or the future, nor can we interfere with it in these states. Our observations and activity are limited to the 'reality' of the present moment or 'now', and this moment apparently travels through time into the future, revealing what it holds and allowing what has gone to pass into history.

It will be appreciated that if the future did not already exist in some form, then the present moment would move forward into a blank area of non-existence, and to achieve the obvious reality of the universe as the present moment passed into the future would require the continuous creation of everything. Accordingly, it is accepted that the world-lines or tracks of all material objects stretch into both future and past. (A world-line or track is the line in space-time traced out by a material particle.) It is only our inability to apply conscious attention to them which gives us the impression that they are unreal.

The fact that the present moment is the only reality between an unreal past and an unreal future raises a difficulty. No matter how short we assume the present moment to be, when it begins there will always have to be a period still in the future, whilst before it ends a part of it has passed into history. The present moment has no duration. It is like the line which divides an advancing area of light from the shadow into which it moves. Mathematically, the present moment exists but is infinitely short, which means that no action can take place within it. It would thus appear that we must live our lives in an unreal future and an unreal past, which is obviously absurd.

Several theories have been put forward to resolve this paradox, usually based on the device known as the 'specious present', in which somehow the present moment is granted a kind of duration of a finite time, so that the beginning and end of the period are not future or past to an action taking place within it. It has been claimed, from the materialist standpoint, that such a situation is possible because the appreciation of the passing of time is a psychological phenomenon, but this theory has no substance. A psychological function is simply a specific form of physiological function, and a physiological function is a physical action, and there is no aspect of the physical appreciation of time in which there can be a duration which is neither past nor future. The paradox arises from trying to relate appreciation of physical time to a reaction in the physical brain, and if this approach is abandoned it is possible to resolve the paradox.

It may be possible theoretically to have direct knowledge of a future event, but if, as a result, steps are taken to prevent that event, then it could not possibly have been a future event and could not have been foreseen. However, as already mentioned, there is a flaw in this line of reasoning and I will use a personal precognitive experience (fictional) of my friend Harry to expose it. His experience is similar to many accounts in the literature.

On 10th June last, all the known physical conditions affecting Harry's future clearly led up to the fact that on 30th he would fall overboard from a boat taking part in a regatta on the local river at 3.30 p.m. as it passed the clock tower by the bridge. There is no question about the veracity of such a possibility. The French mathematician Pierre Laplace claimed that if the position and movement of every particle of matter in the universe were known and adequate calculating facilities were available, it would be possible to calculate the state of the entire universe at any moment in its future or past. We shall be content simply with the operation of all physical factors affecting Harry's future, and calculations show that Harry will indisputably be involved in the boat accident.

It has been claimed that the uncertainty of quantum mechanics can nullify the certainty of such deterministic forecasting, but, as quantum theory is based on atomic and sub-atomic reactions, I think we can safely disregard any quantum effect in Harry's case. It is interesting to note that Harry's world-lines indicating his activity in the future showed that on 20th he would be sitting in his garden watching the day go by, and that he later intended to go to the sailing club to make arrangements for 30th. However, it seems that whilst having his rest he dozed off and had a dream or hallucination of the events which were destined to take place on 30th. Harry stated that he had a clear picture in front of him of the accident in which he was involved, and of the surroundings, and as a result he decided to abandon his boat trip and go hiking instead.

Unless this situation can be explained by an acceptable hypothesis, the deterministic rejection of precognition must be regarded as valid; conversely, if a satisfactory theory can be put forward, with supporting evidence, to explain how and why Harry had his vision, then serious consideration must be given to the possibility of precognition.

The questions which must be answered in this context are:

  1. What is the characteristic of time which would allow such an event to take place? It is a phenomenon which is regarded as impossible with physical time.
  2. Could this aspect of time resolve the paradox of the 'non-real' present moment?
  3. If so, does it extend beyond the present moment into the future?
  4. If it does so, what prevents it from constantly wandering into different areas of the future?
  5. If the foreseen event never took place, why and how did the percipient experience it ?
  6. What does a percipient actually 'see' in a precognitive vision?

We are aware of the passing of time because we experience the sensation of time passing. Similarly, we are aware of the colour of a flower because we experience the sensation of colour. As a result, we perceive the colour, and in the same way we perceive the passage of time. Awareness of the passage of time, then, would appear to be a perceptual experience, probably taking place in the same stratum of consciousness as other perceptual activities.

Another characteristic of the passage of time which is also shown by perceptual activity is control under hypnosis. As is well known, under hypnosis perceptual images and sensations relating to the five senses can be created by consciousness, irrespective of any sensory system which may be functioning at the same time. The restraint normally exerted by cerebral association on perceptual activity appears to be lacking completely, suggesting that this function operates independently of the brain. In the same way, the restraint normally exerted by cerebral association on temporal activity appears to be removed completely, and this suggests that the two phenomena are closely related. For example, extensive experimental work on time appreciation under hypnosis has been carried out (Cooper & Erickson, 1952; Cooper, 1952; Cheek & LeCron, 1968) and it has been shown that under these conditions the perceptual activity involved can operate at a speed far in excess of that of which the brain is normally capable, which indicates a function operating independently of the brain.

It has been pointed out (Roberts, 1992) that visual perception has a unique characteristic in that everybody appears to have an identical perceptual faculty. If everybody with normal eyesight looked at the same red rose they would all have exactly the same perceptual image, irrespective of their size, race, sex, age, colour, etc., and of the usual differences in all their physiological attributes. The same phenomenon arises with the appreciation of time — everybody is aware of exactly the same present moment. If experiencing the present moment is a physiological activity, then the brains of everybody function at precisely the same speed throughout life. It is as though everybody in the world has the same heart-beat rate of precisely 78 per minute, all through their lives. This, of course is utterly impossible.

It might be claimed that appreciation of time is the result of an advancing present moment, affecting everybody in the same way at the same instant, just as, for example, an earthquake affects everybody in the locality at the same time, irrespective of their physiological differences. This is not the case. Physical time is not absolute; it does not make a distinction between past and future and therefore has no present moment. As Davies (1983) points out: "There can be no unanimous agreement about the choice of 'now'. There is no universal 'present moment' ". The present moment is a concept of individual consciousness, yet it is identical in everybody.

It should be noted that although the theory of relativity maintains that if two people are moving relative to each other their present moments do not coincide, the difference in everyday life is infinitesimal. It is therefore undetectable and does not alter the fact that conscious appreciation of the present moment is the same for everybody. In addition, it might be claimed that some drugs appear to interfere with the normal rate of time appreciation, and therefore that this phenomenon must be dependent on cerebral action, but this is no more valid than the claim that excess alcohol causing distorted vision is a proof that visual perception is physiological.

There are thus significant grounds for accepting that appreciation of the passage of time is a phenomenon at that level of consciousness in which all other perceptual activity takes place. It is, in effect, simply an aspect of perception, and acceptance of this approach enables the problem of precognition, and other anomalies of time, to be viewed from a more pragmatic point of view than has generally been used.

A significant volume of evidence has been put forward (Roberts, 1991) suggesting that perception is a non-physiological phenomenon which takes place in a level of consciousness independent of the brain. If time appreciation is an aspect of perception, then it also is a non-physiological activity and this represents the characteristic of time necessary for the operation of precognition and the resolution of the present-moment paradox, as raised in Questions 1 and 2. It is interesting to note the results of applying these factors to precognition.

Conscious awareness in visual perception is not limited to a spot or a line; it is able to appreciate an area. Conscious awareness in aural perception is not limited to a single note; it can respond to a wide range of frequencies, either in succession or simultaneously. There is no reason to assume that when consciousness apprehends a temporal dimension its activity is limited to just a point on a world-line; instead, it will cover an area of temporal data corresponding to the scope of visual and aural perception. When a length of the temporal dimension is being observed by consciousness, we experience the sensation of duration. It is, in fact, what we regard as the present moment, but it is not the paradoxical present moment of physical time. It will thus be seen that a non-physiological element in consciousness can explain the duration of the present moment and give the answer to Question 2.

Although consciousness can be aware of what is in the 'past' and 'future', it is limited to the brief period of the present moment and does not wander off into distant realms of time. This is almost certainly the result of evolutionary necessity, closely parallel to that which took place with visual perception. In that case it would appear that the level of consciousness in which visual images are created had to learn during evolutionary development how to respond to retinal signals. It had to adopt this technique because there was no physical link between the visual cortex pattern and the agency creating the image, yet retinal activity and the resulting perceptual images had to agree precisely in every detail, as otherwise life would obviously be impossible. In the same way, the developing stratum of consciousness perceiving the passage of time had to learn to operate within the rigid limits of the present moment, as freedom for consciousness to venture unrestricted into 'past' and 'future' would obviously make life equally impossible. This, then, is the answer to Question 4. Conscious appreciation of past and future is limited to the brief period of the present moment as the result of a necessary evolutionary step.

It has been pointed out (Roberts, 1992) that with the creation of perceptual images from retinal data there were rare occasions when the established and rigid perceptual response to specific data broke down, and the perceptual image was distorted or even replaced by a different image originating from a non-sensory source. It could well be that the mechanism controlling the perception of time might likewise become faulty or break down, or perhaps consciousness might be rendered less able to control it in the dream state, and as a result the ability to apprehend world-lines might extend temporarily beyond the limits of the normal present moment into the deeper future or past.

There are, of course, differences between world-lines extending into the past and those into the future, at least as far as cerebral world-lines are concerned. It is possible that the world-lines of the particles comprising, for example, a mountain are not affected by the passage of what we regard as the present moment, and cannot be altered by any factor other than physical force. However, we are concerned here with cerebral world-lines, which are subject to the influence of conscious activity. The fact that cerebral world-lines into the future behave differently from past lines can be shown by a simple experiment. The constraint of the present moment on a hypnotized subject is largely removed. Conscious attention can be directed to any stage of past lines and their configuration can be apprehended in great detail; and the recall appears to be equally effective at all points in the past. However, when the same technique is applied to the future only the vaguest indication of future world-lines has ever been achieved. Either a different, and as yet unknown, technique must be used in probing into the future or, as is much more likely, future world-lines of the brain become more and more indefinite the deeper the investigation.

It would thus appear that conscious appreciation of time involves the following qualities: —  

  1. It is a form of perception with properties similar to perceptual activity arising from both sensory and non-sensory sources.
  2. As there is significant evidence suggesting that perception is a non-physiological phenomenon, there is reason to accept time appreciation as non-physiological.
  3. If this is so, it follows that a period of some duration within the present moment is possible.
  4. his sensation of duration is due to observation by consciousness, not only of the infinitely small point separating past and future, but also of world-lines extending into both past and future.
  5. The mechanism limiting this duration to the brief period of the present moment is a product of evolutionary progress.
  6. There are circumstances in which this controlling factor becomes unreliable, and it is then possible for consciousness temporarily to observe world-lines extending further into the future.

 On the basis of these characteristics of time it is possible to put forward a theory of precognition which avoids the intervention paradox. This paradox, which, it is claimed, shows that precognition is impossible, is based on an invalid premise and has a false conclusion. The great weakness is not in the claim that the so-called 'precognitive event' cannot possibly be precognitive, but in failure to recognize that in a physiological system it is quite impossible for such an event to occur at all, and therefore that any conclusion based on its existence is invalid.

An example might illustrate this point. In Harry's case there is one indisputable fact, which is that on 20th Harry decided that on 30th he would go for a walk, and duly did so. He did so because his consciousness became aware of a cerebral pattern showing adverse possibilities for the future. Irrespective of the nature of the presented brain pattern, Harry's response — a change of future action—was a physical action, and any physical action on 20th could be traced back to his brain configuration on 10th. Therefore his brain state on 10th must clearly have included his decision of 20th not to go to the regatta. At the same time, because of his prior decision to participate in the regatta, his brain pattern on 10th must also have included world-lines showing his decision to go to the regatta, with its unfortunate consequence. Obviously there cannot at the same time be two cerebral configurations with future world-lines in direct contradiction to each other. This, then, is the real paradox, but it only arises when one tries to explain apparent precognitive phenomena on a physical basis.

Since it is impossible to deny that Harry went walking on the moors, it must be accepted that his world-lines relating to this event are valid, whilst those concerning the presumed forthcoming accident are ineffective, or even non-existent. This means it was quite impossible for Harry to have had a dream or hallucination or any form of experience originating from cerebral data related to the boating accident. Yet Harry undeniably had such an experience, and the literature shows a voluminous number of similar confirmatory cases.

It would seem that there are only three explanations of this situation. In the first place, all these experiences may be due to chance coincidences, but the billions-to-one odds against this being the case are so remote as to render it totally unacceptable. Secondly, they may all be due to fraudulent or mistaken recording, which implies that a very substantial number of observers (of otherwise the highest integrity or intelligence) have deliberately falsified their records. Thirdly, they may be accurate descriptions of a phenomenon not yet understood, and it is this option which will be considered.

It will be seen that the anomaly arises from the claim, for which there appears to be no evidence, that the observation by consciousness of Harry's future world-lines is a physical function. If this stipulation is abandoned, there cannot be any cerebral trace before 20th of Harry's decision, on that date, to go walking. Only the original world-lines of the forthcoming regatta and accident exist, and the paradox is resolved. It follows that on that date all the world-lines relating to Harry's activities would, on 10th, indisputably indicate an accident on 30th. There would be no sign whatsoever of any intervention prior to 30th and the accident could virtually be regarded as a pre-determined future event, meeting all the criteria of such a situation.

However, if some agency which normally does not intervene becomes effective on 20th and modifies Harry's world-lines so that henceforth the accident is prevented, then we would have the situation where a pre-determined and established future state is modified as a result of foreknowledge of that state. In other words, we would have a modus operandi for precognition without falling foul of the intervention paradox.

The question then arises as to the nature of such an entity and how it operates. There can be little doubt but that it is an area of consciousness, and if it was not influencing Harry's brain pattern before 20th there is no avoiding the conclusion that it is non-physiological. A physical agency cannot just come into existence in the brain and start exerting control over some area of consciousness. As has already been explained, there are good reasons for accepting that some strata of perceptual consciousness function independently of the brain, i.e. are non-organic. In addition, it has been suggested that whilst in the normal perception of time consciousness observes a limited extension of both the future and the past of the mathematical present moment, there are times when it moves deeper into these regions. This is what happened with Harry on 20th; his conscious attention momentarily moved forward from its normal area of control to the situation which it would normally observe on 30th, and following which step all intervention was carried out without any physical origin.

Let us consider a simple illustration of this principle. Harry is walking along a path at night. He is, in fact, sleep-walking and behaving like an automaton. I am somehow suspended at a height above him and hold him in a spotlight. This not only enables him to be aware of his immediate surroundings, but is the means by which I can control his cerebral activity and receive information from his sensory systems. The small area of light surrounding him does not enable him to see any of the path ahead or what he has left behind.

However, I had a spasm in my arm which caused the spotlight to jump a few metres ahead along the path and landed on a dangerously deep hole. My perceptive faculties immediately became effective and filled in a full picture, as is part of their normal function. It was inevitable that my perceptual image would show Harry falling into the hole, because I believed this would be the case, and there is ample evidence (Roberts, 1989) indicating that perceptual images often consist partly of sensory data and partly of conscious belief. By means of my communicating spotlight I was able to intervene and steer Harry in another direction.

It was a classic model of precognition, which contravened no known laws of science and entailed no intervention paradox. It did, however, illustrate three significant characteristics of precognition. The guiding intelligence concerned was physiologically independent of Harry's brain, its observation of the event was virtually from a four-dimensional position (a point concerning consciousness advocated by many authorities), and in the event of Harry's brain ceasing to function its guiding intelligence did not necessarily have to do likewise.

It is clear that if it is accepted that appreciation of the passage of time is a perceptual phenomenon with characteristics similar to those arising from other sources, both physiological and non-physiological, then we have not only a single rational explanation of precognitive phenomena and the invalidation of the ancient paradox denying its existence, but also a fresh perspective on the fundamental subjects of free will, determinism and dualism.

Ashford, Kindlestown Hill
Delgany, Co. Wicklow


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-         Cooper, L. F. (1952) Time distortion in hypnosis. In LeCron, L. M. (ed.) Experimental Hypnosis. New York : Citadel Press.

-         Cooper, L. F. and Erickson, M. H. (1952) Time distortion in hypnosis II. In LeCron, L. M. (ed.) Experimental Hypnosis. New York: Citadel Press.

-         Davies, P. (1983) God and the New Physics. London & Melbourne: J.M.Dent & Sons.

-         Roberts, F. S. (1989) Some implications of the voluntary control of visual perception. JSPR 56, 309-310.

-         Roberts, F. S. (1991) Some apparently non-cerebral aspects of consciousness. JSPR 58, 31-38.

-         Roberts, F. S. (1992) A possible non-physiological basis for perception and a defence of dualism. JSPR 58, 250-257.