[In part 3, the author spoke about Darwin’s discovery of random variations as a cornerstone in organic evolution. He found that animals and plants would be born with random variations, only the ones that were best suited to the surroundings would survive. This meant that God made more failed designs than correct ones, making him presence redundant.]
We are using in this essay the terms “random variation” time and again. What is it? How did Charles Darwin turn his attention to the phenomenon described by this phraseology? What does it signify in science? If it is random, how does a law appear through this? Is there any causal relation in the random phenomena? Or, does randomness imply lawlessness?
Let us delve into these problems.
To get at the idea of randomness we have to handle some mathematics. Students of mathematics know there is a concept of variable in it. A quantity which assumes different values at different times or in different conditions is called a variable (the adjective is turned into a noun). For example, a man’s age, the time shown in the clock, weights of potatoes in a sac, the size of the fishes, the meter reading in a taxi, the temperature of a place, marks obtained by students in (say) history in a school examination, and so on. It is hardly difficult to guess that these quantities vary from case to case and from time to time. But note that here there are two kinds of variable quantities. The variables like the age of a man, the time shown by a clock, or the taxi meter reading, etc. change with a pattern. They do not rise (or fall, as is relevant) haphazardly but conform to some other kind of order. The person who was aged 53 in 2019 will be 57 this year (2023) without a doubt. The meter reading of a taxi, unless the machine is defective, shows a steady increment at regular intervals.
But the potatoes in a sac, although different in size and weight, do not show any identifiable correlation. That means, looking at the size you may not be able to tell the weight. Neither the seller even. When you purchase prawn or tomato in the market, you will face and/or see the same problem.Quantities like these are called random variables in mathematics.
Although the implicit values of the variables differ from case to case, there are no simple mathematical relations or laws visible among them. At least immediately, on the face value.Then what is the meaning of randomness? Everything whatsoever? Absolute wilderness? Total disorder? Thorough lawlessness? Simply unpredictable?
No, none of these. At least in the mathematical sense.
It implies unplanned, undetermined, without premeditation, so on and so forth. There is determination, but no predetermination.
Consider the case of the dice in Ludo. If it turns out ‘two’ now, there is no certainty that in the next turn you will get ‘three’ or ‘four’. On the other hand, whatever comes, it will show surfaces with markings from one to six. You shall never get a ‘fifteen’ or a ‘twenty seven’. Similarly, take the case of the potatoes in the sac. The weight of a potato may be 37 grams or 54 gram. However it is hardly likely to weigh two kilograms. This type of quantities is called a random variable. However randomness is not synonymous with lawlessness. Random variables also follow certain laws. They are called the law of large numbers, subject to the law of probability. Both of these are under some solid mathematical formulations. These are expressed in the forms of equations with their well defined right hand side equal to the left hand side. Equations entail an order. And hence causality. Some definite causes ensure what is more probable; without a sound cause something is unlikely to occur.
For example, if a person has slightly more than 110 microgram/ml of sugar in his/her bloodstream, it signals the possibility of trouble. Possibility does not imply the immediate occurrence of the danger. The more the proportional quantity of sugar, the greater the likelihood of the danger. If the person is interested to know why, a physician may explain the situation. But he will explain the ensuing troubles in terms of causality, with reference to the salient biochemical and physiological facts, the so called aetiology of diseases. Again for instance, what will turn out in the next move in a game of Ludo? You can’t say for certain. It may come as any from one to six. What cards will one in a Bridge game obtain at a particular shuffle? It is also similarly uncertain. Or, having his/her own cards in hand, a player may not be able to guess the cards in the hands of his/her partner.
With so much ignorance how does the game then proceed? With the help of the law of probability. In a multiple of moves, a six is sure to come up in the Ludo. Just so, in the periodic shuffling of the cards one may expect some cards more often than not. This knowledge propels the game forward. The more does one understand the role of probability the better may one play. This phenomenon where a variable assumes different undetermined values is known as random variation. This concept had crept into mathematics in Europe ever since the seventeenth century to tackle the problem of gambling. Many theorems, functions and equations were gradually born out of that practice in the last four hundred years. But it did not find use beyond pure mathematics till the middle of the nineteenth century; or to put it more succinctly, till Charles Darwin. With the introduction of the
concept of random variation, Darwin showed two things:
1) Variations on which natural selection works are random and reject teleology;
2) in the long run, some varieties being successful in adaptation and later in selection is almost certain, which ensures evolution proceeds.
It is thus that on the one hand the species are stable and do not change on and often; on the other, evolution is also possible in and as a long term process. Both these processes brook no interference of Providence; on the contrary, bringing in the almighty there jeopardizes explanations of both phenomena.
In other words, the design argument went against the very purpose of the men who had proposed it. If you conceive of God as the grand designer of the successful candidates, you have no way but to attribute to Him the designs of the unsuccessful species too, the number of which overwhelm the number of the former by a multiple factor. That grossly undermines the power and knowledge of a superbeing. But the ideas of random variation and of selection working upon it explicate both without the least anomaly.
Consider the case of earthquake in Syria (February 2023), in which about fifteen thousands of people died under the heaps of the crumbled buildings. One cannot obviously elicit this as a sample of mercifulness of God. And even if one tries, the surviving relations of the killed will scarcely accept the thesis. Now suppose someone goes to cite the two kids strangely surviving the grave of debris as an example of God’s magnanimity. Directly someone else, in line with the son in Ingersoll’s story, may ask: Did Herr God think of the two kids only and forgot about the others? IT WOULD LOOK VERY BAD. One had better keep silent in such cases. Or a devotee may argue like the simple minded Ramakrishna: How can we fathom the will of God? It’s OK then.
The truth is that large scale destruction of life and properties in the event of an earthquake is a natural occurrence, although some may escape death on certain rare concatenation of things. This exception is also a random eventuality, similar to what happens in natural phenomena like storm, thunder bolt, cyclone, tsunami, flood, landslide, and so on. We may attach anthropomorphic terms like catastrophe, calamity, disaster, etc. to any of them from our survival point of view, but they still are merely some natural phenomena.
Thus the credit of introducing the idea of random variation into the fields of science goes to Darwin. He for the first time showed that natural phenomena occur out of nature’s intrinsic processes, and not by any human or superhuman dicta, neither by virtue of any pre-plan or pre-designed order. He could not express the matter in mathematical form, in terms of probability, for he had no grounding for that. Once the idea got entry in the court of scientific knowledge, it was extended further by Gregor Mendel in his theory of heredity, and that with a statistical formulation. Soon it found application in the field of physics through the works of James Clerk Maxwell and Ludwig Boltzmann. Five decades later when quantum mechanics appeared on the scene, probability became its fundamental spoken language.
The author is a science writer. He is the General Secretary for Centre for Studies in Science and Society [CESTUSS], Kolkata.
Sources:
Pietro Corsi (2009), “Evolution pioneers: Lamarck’s reputation saved by his zoology”; Nature 461, 167 (2009).
J. B. Lamarck (1914), Zoological Philosophy: An exposition with regard to the Natural History of Animals; Macmillan & Co., London. Georgi Plekhanov (1976), “On the So-called Religious Seekings in Russia”; Selected Philosophical Works, Vol. III; Progress Publishers, Moscow.
Jacques Roger (1986). “The Mechanist Conception of Life”. In David C. Lindberg, and Ronald L. Numbers (1986 eds.), God and Nature: Historical Essays on the Encounter Between Christianity and Science. University of California Press.
