Emergence

By Michael Colebrook

Everything is best understood by its constitutive causes. For, as in a watch or some such small engine, the matter, figure and motion of the wheels cannot well be known except it be taken asunder and viewed in parts.

Thomas Hobbes

Emergence means complex organizational structure growing out of simple rules. Emergence means stable inevitability in the way certain things are. Emergence means unpredictability, in the sense of small events causing great and qualitative changes in larger ones. Emergence means the fundamental impossibility of control. Emergence is a law of nature to which humans are subservient.
Robert Lauchlin. A Different Universe.

In effect, there seems to be no end to the emergence of emergents. Therefore, the unpredictability of emergents will always stay one step ahead of the ground won by prediction. As a result, it seems that emergence is now here to stay.

 

Jeffery Goldstein

The fundamental premise relating to emergent phenomena is that wholes can contradict Hobbes’ dictum and be more than the sums of their parts. In any system for which this is true, that element which constitutes the ‘more than’ is an emergent property of the whole system and has to be regarded as the outcome of a creative process. Emergent phenomena cannot be described in terms of a chain of causality. They do not have a cause. They just happen. Both Ian Stewart and Stuart Kauffman (see References) emphasise that there is as yet no sound scientific theory of emergence.

It might be thought that, given these criteria, emergent phenomena were relatively rare and special features of the created order. In fact we are surrounded by them. It could be claimed that the human sensory system was designed specifically to provide awareness of emergent phenomena. Physics tells us that a chair is made up of a collection of very, very small particles separated by distances that are enormous compared to their size. By far the largest constituent of a chair is empty space. And yet, we can see and feel a chair and we are confident that if we should sit on one, we would not finish up on the floor. The solidity of solids is an emergent phenomenon and is a function of the relationships between the particles that physics tells us about. The solidity of solids is not an illusion, it is as real as the particles which constitute the solid. The properties of solids such as density, hardness, strength, elasticity etc. cannot be reduced to the properties of constituent particles because they depend on the relationships between them. The properties of solids are as real and fundamental with respect to solids as are the properties of the so-called fundamental particles.

There can be layers of emergent properties. Forests exhibit emergent properties based on relationships between living organisms. Living organisms show emergent properties based on relationships between complex chemicals. Complex chemicals show emergent properties based on the relationships between atoms. Atoms show emergent properties based on the relationships between sub-atomic particles.

Given the ubiquity of emergent processes and they way in which they are organised into progressive sequences, it can be argued that they are the means by which the universe creates itself.

If this makes it sound too easy to create a universe, emergent properties are not entirely free to make things up as they go. They are subject to significant constraints, such as the universal conservation laws which state the matter and energy can neither be created nor destroyed. They can only proceed by creating new patterns of relationship using pre-existing materials. This is one of the reasons why it took 10,500,000,000 years for life to emerge on planet Earth. As D H Lawrence rightly says:

The history of the cosmo
is the history of the struggle of becoming.

And the history of the struggle of becoming is substantially the history of emergent phenomena. It is one of the paradoxes of modern science that in spite of everything that is known and understood about the cosmos there is no clear general theory of emergence. This is because science has on the whole adopted Hobbes’ dictum and has been concerned primarily with seeking explanations of phenomena in terms of the behaviour of their parts. The study of emergent phenomena requires a top-down as opposed to the Hobbesean bottom-up approach.

One of the concepts that has been useful in attempts to give shape to studies of emergent phenomena is that of symmetry. In terms of the scientific definition of symmetry the surface of a still body of water exhibits perfect two-dimensional symmetry because it is the same in all possible directions in a two dimensional plane. If you drop a stone into the water the result is the formation of a set of circular ripples which are symmetrical about a centre (the point where the stone was dropped), these ripples exhibit radial symmetry in that they look the same in all directions but only from the central point. They exhibit a reduced symmetry compared with that of the undisturbed surface. Although there is an apparent increase in ordered pattern on the surface of the water the original symmetry has been broken. In general, increase in order and pattern is associated with broken symmetries. A good example of the emergence of order associated with symmetry breaking is provided by Langton’s Ant. The apparently chaotic pattern produced by the first 10,000 moves by the ant can be said to show perfect two-dimensional symmetry (at least away from the edges and in a statistical sense) in that it looks the same in all directions. The highway represents a breaking of this symmetry to produce a more ordered state. Both the chaotic and the ordered states are intrinsic features of the behaviour of Langton’s Ant which is governed by specific but very simple rules. The ordered state represents an emergent property associated with symmetry breaking. It needs to be stressed that symmetry breaking is a descriptive feature of emergent phenomena. It does not constitute an explanation or even a contribution towards one.

Another feature of emergent phenomena is coherence. When a stone is dropped into still water, some of its energy is transferred to the water and results in the formation of a series of waves which involve the coherent behaviour of millions and millions of water molecules. Due to the viscosity of the water the waves soon dissipate, their energy being converted to heat. The waves are caused by the energy transferred by the falling stone but the form of the waves is the result of internal and intrinsic relationships between the molecules of water. With Langton’s Ant the highway represents a coherent pattern of behaviour of the ant, in this case a loop of 104 moves, compared with the previous chaos.

In this case the pattern of the highway does not dissipate because there is a continuous input of energy from the computer on which the ant programme is running.

Another form of cellular automaton involving simple rules and devised by John Horton Conway (see Conway’s Game of Life) can exhibit a wide range of coherent behaviours involving closed loops and moving patterns as well as chaotic and ordered sequences of moves. As with Langton’s Ant the outcome of any but the simplest of initial patterns is unpredictable and small changes can produce very different outcomes. One of the interesting features is that it is possible the establish an initial state consisting of a set of moving patterns called gliders which interact to produce a pattern which then generates a stream of gliders, coming close to being a self-reproducing system.

What these cellular automaton games show is that systems with simple rules can produce unpredictable results and some of these can take the form of quite complex emergent features.

Let me finish this brief introduction to emergent phenomena with an example from the real world. If you take a bundle of fibres and spin them together, over and under each other, and you get yarn. Take yarns and spin them together, over and under each other, and you get string. Spin strings together, over and under each other, and you get rope. This is an age-old craft; the earliest preserved bit of rope was found in the caves of Lascaux and dates from about 15,000 BC.

Yarn, string and rope possess properties of length, strength, flexibility and durability which are potentially present within a bundle of fibres but their manifestation depends on the internal structural relationships between the fibres. Yarn and string and rope are more than the sums of their parts, they are emergent entities, and over and under is an emergent rule or principle. As often happens, emergent entities provide opportunities for further emergent phenomena. And in this case these involve the same rule of over and under together with developments of it.

The classic Ashley Book of Knots contains diagrams and descriptions of 3854 things that can be done with rope and string, virtually all of which involve some version of over and under.

Woven materials are another example of emergence based on yarns combined according to the rule of over and under. Starting with a simple weave of over one and under one, there is an almost infinite variety of other options as the strict form of the rule is relaxed to allow other combinations of overs and unders. Weavers experiment and probe the limits of the constraints imposed by the basic rule. But it can never be totally neglected or the resulting material will simply fall apart.

The rule of over and under applied to fibres is an example of emergence essentially created by human ingenuity in which emergence builds on emergence and in which the application of a simple principle can lead to an almost endless variety of outcomes.

Probably the most significant of all emergent phenomena is the mind that you are using to read and I hope understand this account of emergent phenomena. It has taken ‘the struggle of becoming’ some fourteen billion years to produce it.

References

Clifford Ashley. The Ashley Book of Knots (Faber & Faber, 1947).
Brian Goodwin. How the Leopard Changed Its Spots (Phoenix, 1995)
Erich Jantsch. The Self-Organising Universe (Pergamon Press, 1980).
Michael Colebrook How Things Come To Be (GreenSpirit Press, 2006).
Stuart Kauffman. At Home in the Universe (Viking, 1995).
Stuart Kauffman. Investigations (OUP, 2000).
Ricard Solé & Brian Goodwin. Signs of Life (Basic Books, 2000).
Ian Stewart & Jack Cohen. Figments of Reality (CUP, 1997).