Lateral Thinking

by Edward de Bono

  Vertical thinking is analytical, lateral thinking is provocative

  One may consider three different attitudes to the remark of a student who had come to the conclusion: ‘Ulysses was a hypocrite.’.

  1. ‘You are wrong, Ulysses was not a hypocrite.’

  2. ‘How very interesting, tell me how you reached that conclusion.’

  3. ‘Very well. What happens next? How are you going to go forward from that idea?’

  In order to be able to use the provocative qualities of lateral thinking one must also be able to follow up with the selective qualities of vertical thinking.

  Vertical thinking is sequential, lateral thinking can make jumps

  With vertical thinking one moves forward one step at a time. Each step arises directly from the preceding step to which it is firmly connected. Once one has reached a conclusion the soundness of that conclusion is proved by the soundness of the steps by which it has been reached.

  With lateral thinking the steps do not have to be sequential. One may jump ahead to a new point and then fill in the gap afterwards. In the diagram below, vertical thinking proceeds steadily from A to B to C to D. With lateral thinking one may reach D via G and then having got there may work back to A.

  When one Jumps right to the solution then the soundness of that solution obviously cannot depend on the soundness of the path by which it was reached. Nevertheless the solution may still make sense in its own right without having to depend on the pathway by which it was reached. As with trial-and-error a successful trial is still successful even if there was no good reason for trying it. It may also happen that once one has reached a particular point it becomes possible to construct a sound logical pathway back to the starting point. Once such a pathway has been constructed then it cannot possibly matter from which end it was constructed — and yet it may only have been possible to construct it from the wrong end. It may be necessary to be on the top of a mountain in order to find the best way up.

  With vertical thinking one has to be correct at every step, with lateral thinking one does not have to be

  The very essence of vertical thinking is that one must be right at each step. This is absolutely fundamental to the nature of vertical thinking. Logical thinking and mathematics would not function at all without this necessity. In lateral thinking however one does not have to be right at each step provided the conclusion is right. It is like building a bridge. The parts do not have to be self-supporting at every stage but when the last part is fitted into place the bridge suddenly becomes self-supporting.

  With vertical thinking one uses the negative in order to block of certain pathways. With lateral thinking there is no negative

  There are times when it may be necessary to be wrong in order to be right at the end. This can happen when one is judged wrong according to the current frame of reference and then is found to be right when the frame of reference itself gets, changed. Even if the frame of reference is not changed it may still be useful to go through a wrong area in order to reach a position from which the right pathway can be seen. This is shown diagrammatically below. The final pathway cannot of course pass through the wrong area but having gone through this area one may more easily discover the correct pathway.

  With vertical thinking one concentrates and excludes what is irrelevant, with lateral thinking one welcomes chance intrusions

  Vertical thinking is selection by exclusion. One works within a frame of reference and throws out what is not relevant. With lateral thinking one realizes that a pattern cannot be restructured from within itself but only as the result of some outside influence. So one welcomes outside influences for their provocative action. The more irrelevant such influences are the more chance there is of altering the established pattern. To look only for things that are relevant means perpetuating the current pattern.

  With vertical thinking categories, classifications and labels are fixed, with lateral thinking they are not

  With vertical thinking categories, classifications and labels are useful only if they are consistent, for vertical thinking depends on identifying something as a member of some class or excluding it from that class. If something is given a label or put into a class it is supposed to stay there. With lateral thinking labels may change as something is looked at now in one way and now in another. Classifications and categories are not fixed pigeonholes to aid identification but signposts to help movement With lateral thinking the labels are not permanently attached but are used for temporary convenience.

  Vertical thinking depends heavily on the rigidity of definitions just as mathematics does on the unalterable meaning of a symbol once this has been allocated. Just as a sudden change of meaning is the basis of humour so an equal fluidity of meaning is useful for the stimulation of lateral thinking.

  Vertical thinking follows the most likely paths, lateral thinking explores the least likely

  Lateral thinking can be deliberately perverse. With lateral thinking one tries to look at the least obvious approaches rather than the most likely ones. It is the willingness to explore the least likely pathways that is important for of ten there can be no other reason for exploring such pathways. At the entrance to an unlikely pathway there is nothing to indicate that it is worth exploring and yet it may lead to something useful. With vertical thinking one moves ahead along the widest pathway which is pointing in the right direction.

  Vertical thinking is a finite process, lateral thinking is a probabilistic one

  With vertical thinking one expects to come up with an answer. If one uses a mathematical technique an answer is guaranteed. With lateral thinking there may not be any answer at all Lateral thinking increases the chances for a restructuring of the patterns, for an insight solution. But this may not come about Vertical thinking promises at least a minimum solution. Lateral thinking increases the chances of a maximum solution but makes no promises.

  If there were some black balls in a bag and just one white ball the chances of picking out that white ball would be low. If you went on adding white balls to the bag your chances of picking out a white ball would increase all the time. Yet at no time could you be absolutely certain of picking out a white ball. Lateral thinking increases the chances of bringing about insight restructuring and the better one is at lateral thinking the better are the chances. Lateral thinking is as definite a procedure as putting more white balls into the bag but the outcome is still probabilistic. Yet the pay off from a new idea or an insight restructuring of an old idea can be so huge that it is worth trying lateral thinking for there is nothing to be lost. Where vertical thinking has come up against a blank wall one would have to use lateral thinking even if the chances of success were very low.

  Summary

  The differences between lateral and vertical thinking are very fundamental. The processes are quite distinct. It is not a matter of one process being more effective than the other for both are necessary. It is a matter of realizing the differences in order to be able to use both effectively.

  With vertical thinking one uses information for its own sake in order to move forward to a solution.

  With lateral thinking one uses information not for its own sake but provocatively in order to bring about repatterning.

  Attitudes towards lateral thinking 3

  Because it is so very different from vertical thinking many people feel uncomfortable about lateral thinking. They would rather feel that it is just part of vertical thinking or that it does not exist. Some of the more standard attitudes are shown below.

  Although one appreciates the effectiveness of insight solutions and the value of new ideas there is no practical way these can be brought about One can only wait for them and recognize them after they have happened

  This is a negative attitude which neither takes account of the insight mechanism nor of the information imprisoned in cliché patterns. Insight is brought about by alterations in pattern sequence brought about by provocative stimulation* and lateral thinking provides such stim
ulation. Information imprisoned in old cliché patterns can often come together in a new way of its own accord once the pattern is disrupted. It is a function of lateral thinking to free information by challenging cliché patterns. To regard insight and innovation as a matter of chance does not explain why some people are consistently able to generate more ideas than others. In any case one can take steps to encourage a chance process. The effectiveness of lateral thinking for generating new ideas can be shown experimentally.

  Whenever a solution is said to have been reached by lateral thinking there is always a logical pathway by which the solution could have been reached. Hence what is supposed to be lateral thinking is no more than a plea for better logical thinking

  It is quite impossible to tell whether a particular solution was reached by a lateral or vertical process. Lateral thinking is a description of a process not of a result Because a solution could have been reached by vertical thinking does not mean that it was not reached by lateral thinking.

  If a solution is acceptable at all then by definition there must be a logical reason for accepting it. It is always possible to describe a logical pathway in hindsight once a solution is spelled out. But being able to reach that solution by means of this hindsight pathway is another matter. One can demonstrate this quite simply by offering certain problems which are difficult to solve and yet when solved the solution is obvious. In such cases it is impossible to suppose that what made the problem difficult was lack of the elementary logic required.

  It is characteristic of insight solutions and new ideas that they should be obvious after they have been found. In itself this shows how insufficient logic is in practice, otherwise such simple solutions must have occurred much earlier. In absolute terms it is impossible to prove that a logical pathway could not have been taken if one can be shown in hindsight (except by reference to the mechanics of information handling in the mind). In practical terms however it is quite obvious that the hindsight demonstration of a logical pathway does not indicate that the solution would have been reached in this way.

  Since all effective thinking is really logical thinking then lateral thinking is just a part of logical thinking

  This objection may seem to be just a semantic quibble. Obviously it does not matter at all whether lateral thinking is regarded as distinct from logical thinking or as part of logical thinking so long as one understands its true nature. If by logical thinking one just means effective thinking then lateral thinking must obviously be included. If by logical thinking one means a sequence of steps each of which must be correct then lateral thinking is clearly distinct.

  If the objection takes into account the information handling behaviour of the mind then it becomes more than a semantic quibble. For in terms of this behaviour it is logical to be illogical. It is reasonable to be unreasonable. If this was not so then I would not be writing a book about it. Here again however one is using logical in terms of ‘effective’ and not as the operational process we know.

  In practice the inclusion of lateral thinking under logical thinking only blurs the distinction and tends to make it unusable — but not unnecessary.

  Lateral thinking is the same as inductive logic

  This argument is based on the distinction between deductive and inductive logic The assumption is that anything which is different from deductive logic must be the same as anything else which is also different from deductive logic There is some resemblance between inductive logic and lateral thinking in that both work from outside the framework instead of from within it Even so lateral thinking can work from within the framework in order to bring about repatterning by such processes as reversal, distortion, query, turning upside down etc. Inductive logic is essentially reasonable: one tries just as hard to be right as in deductive logic. Lateral thinking however can be deliberately and self-consciously unreasonable in order to provoke a new pattern. Both inductive and deductive logic are concerned with concept forming. Lateral thinking is more concerned with concept breaking, with provocation and disruption in order to allow the mind to restructure patterns.

  Lateral thinking is not a deliberate way of thinking at all but a creative gift which some people hove and others do not

  Some people may be better at lateral thinking just as some people may be better at mathematics but this does not mean that there is not a process which can be learned and used. It can be shown that lateral thinking can make people generate more ideas and by definition gifts cannot be taught. There is nothing mysterious about lateral thinking. It is a way of handling information.

  Lateral thinking and vertical thinking are complementary

  Some people are unhappy about lateral thinking because they feel that it threatens the validity of vertical thinking. This is not so at all. The two processes are complementary not antagonistic. Lateral thinking is useful for generating ideas and approaches and vertical thinking is useful for developing them. Lateral thinking enhances the effectiveness of vertical thinking by offering it more to select from. Vertical thinking multiplies the effectiveness of lateral thinking by making good use of the ideas generated.

  Most of the time one might be using vertical thinking but when one needs to use lateral thinking then no amount of excellence in vertical thinking will do instead. To persist with vertical thinking when one should be using lateral thinking is dangerous. One needs some skill in both types of thinking.

  Lateral thinking is like the reverse gear in a car. One would never try to drive along in reverse gear the whole time. On the other hand one needs to have it and to know how to use it for manoeuvrability and to get out of a blind alley.

  Basic nature of lateral thinking 4

  In Chapter Two the nature of lateral thinking was indicated by contrasting it with vertical thinking. In this chapter the basic nature of lateral thinking is indicated in its own right.

  Lateral thinking is concerned with changing patterns

  By pattern is meant the arrangement of information on the memory surface that is mind. A pattern is a repeatable sequence of neural activity. There is no need to define it any more rigidly. In practice a pattern is any repeatable concept, idea, thought, image. A pattern may also refer to a repeatable sequence in time of such concepts or ideas. A pattern may also refer to an arrangement of other patterns which together make up an approach to a problem, a point of view, a way of looking at things. There is no limit to the size of a pattern. The only requirements are-that a pattern should be repeatable, recognizable, usable.

  Lateral thinking is concerned with changing patterns. Instead of taking a pattern and then developing it as is done in vertical thinking, lateral thinking tries to restructure the pattern by putting things together in a different way. Because the sequence of arrival of information in a self-maximizing system has so powerful an influence on the way it is arranged some sort of restructuring of patterns is necessary in order to make the best use of the information imprisoned within them.

  In a self-maximizing system with a memory the arrangement of information must always be less than the best possible arrangement

  The rearrangement of information into another pattern is insight restructuring. The purpose of the rearrangement is to find a better and more effective pattern.

  A particular way of looking at things may have developed gradually. An idea that was very useful at one time may no longer be so useful today and yet the current idea has developed directly from that old and outmoded idea. A pattern may develop in a particular way because it was derived from the combination of two other patterns but had all the information been available at one time the pattern would have been quite different A pattern may persist because it is useful and adequate and yet a restructuring of the pattern could give rise to something very much better.

  In the diagram overleaf two pieces come together to give a pattern. This pattern then combines with another similar pattern in a straightforward manner. Without the addition of any new pieces the pattern can suddenly be restructured to give a much be
tter pattern. Had all four pieces been presented at once this final pattern is the one that would have resulted, but owing to the sequence of arrival of the pieces it was the other pattern that developed.

  Lateral thinking is both on attitude and a method of using information

  The lateral thinking attitude regards any particular way of looking at things as useful but not unique or absolute. That is to say one acknowledges the usefulness of a pattern but instead of regarding it as inevitable one regards it as only one way of putting things together. This attitude challenges the assumption that what is a convenient pattern at the moment is the only possible pattern. This attitude tempers the arrogance of rigidity and dogma. The lateral thinking attitude involves firstly a refusal to accept rigid patterns and secondly an attempt to put things together in different ways. With lateral thinking one is always trying to generate alternatives, to restructure patterns. It is not a matter of declaring the current pattern wrong or inadequate. Lateral thinking is never a judgement. One may be quite satisfied with the current pattern and yet try to generate alternative patterns. As far as lateral thinking is concerned the only thing that can be wrong with a pattern is the arrogant rigidity with which it is held.

  In addition to being an attitude, lateral thinking is also a particular way of using information in order to bring about pattern restructuring. There are specific techniques which can be used deliberately and these will be discussed later. Underlying them all are certain general principles. In lateral thinking information is used not for its own sake but for its effect. This way of using information involves looking forward not backward: one is not interested in the reasons which lead up to and justify the use of a piece of information but in the effects that might follow such a use. In vertical thinking one assembles information into some structure, bridge or pathway. The information becomes part of the line of development In lateral thinking information is used to alter the structure but not to become part of it.