Of Clouds and Clocks

There are lots of things, natural processes and natural phenomena, which we may place between these two extremes—the clouds on the left, and the clocks on the right. The changing seasons are somewhat unreliable clocks, and may therefore be put somewhere towards the right, though not too far. I suppose we shall easily agree to put animals not too far from the clouds on the left, and plants somewhat nearer to the clocks. Among the animals, a young puppy will have to be placed further to the left than an old dog. Motor cars, too, will find their place somewhere in our arrangement, according to their reliability: a Cadillac, I suppose, is pretty far over to the right, and even more so a Rolls-Royce, which will be quite close to the best of the clocks. Perhaps furthest to the right should be placed the solar system.

As a typical and interesting example of a cloud I shall make some use here of a cloud or cluster of small flies or gnats. Like the individual molecules in a gas, the individual gnats which together form a cluster of gnats move in an astonishingly irregular way. It is almost impossible to follow the flight of any one individual gnat, even though each of them may be quite big enough to be clearly visible.

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Like many physical, biological, and social systems, the cluster of gnats may be described as a ‘whole’. Our conjecture that it is kept together by a kind of attraction which its densest part exerts on individual gnats straying too far from the crowd shows that there is even a kind of action or control which this ‘whole’ exerts upon its elements or parts. Nevertheless, this ‘whole’ can be used to dispel the widespread ‘holistic’ belief that a ‘whole’ is always more than the mere sum of its parts. I do not deny that it may sometimes be so. Yet the cluster of gnats is an example of a whole that is indeed nothing but the sum of its parts—and in a very precise sense; for not only is it completely described by describing the movements of all the individual gnats, but the movement of the whole is, in this case, precisely the (vectorial) sum of the movements of its constituent members, divided by the number of the members.

An example (in many ways similar) of a biological system or ‘whole’ which exerts some control over the highly irregular movements of its parts would be a picnicking family—parents with a few children and a dog—roaming the woods for hours, but never straying far from the family car (which acts like a centre of attraction, as it were). This system may be said to be even more cloudy—that is, less regular in the movement of its parts—than our cloud of gnats.

I hope you will now have before you an idea of my two prototypes or paradigms, the clouds on the left and the clocks on the right, and of the way in which we can arrange many kinds of things, and many kinds of systems, between them. I am sure you have caught some vague, general idea of the arrangement, and you need not worry if your idea is still a bit foggy, or cloudy.