No, the title of this post doesn’t mean that I think biologists are criminals. It means that biology is a science without laws (or with very few of them). And by law, of course I mean a construct, generally written in symbolic or mathematical terms, that expresses a theory. Despite the few well known examples of biological theory, such as evolution by natural selection, and some ecological paradigms, biology is notoriously short on theory. I have heard colleagues dismiss any idea of theory in biology as impossible, or non-scientific. And that, I believe, is a serious problem.
An argument could be made that despite the unquestionably rapid pace of scientific progress in biology, our actual level of understanding of the mechanisms that operate in living cells is less profound, less integrated and less easily communicated than it should be given the enormity of the data that has been generated. We are often faced with fragmented fields and subfields of research into an explosive number of subcellular factors, proteins, genes and pathways, each studied in isolation or in association with a very limited subset of the bewildering complexity that is the reality of the cell.
I believe that the reason for the discrepancy between the weight of facts and the breadth of knowledge that we have about cell biology stems from a paucity of theoretical efforts in the field. In all other fields of science, theoretical and experimental work are mutually tied together and tend to progress together, each driving the other, and leading to some degree of an integrated framework of understanding. The absence of any theoretical framework in molecular biology has severely hampered attempts to make sense of the data in an integrative manner.
Biological scientists are not as familiar with theory and its importance as are physicists, and a large part of the problem is the relunctance of molecular biologists to acknowledge the nature of the problem. One response to a plea for more theory in biology is that since biological systems are far more complex than the systems physicists deal with, biologists are forced to focus on relatively narrow areas and cannot hope to address global questions with comprehensive theories. This response betrays the typical biologist’s ignorance of the role of theory in science, which has always been precisely to take large masses of uncoordinated information, which alone seem to suggest unfathomable complexity, and use them to create an orderly, logical, testable and ultimately satisfying understanding of nature that we call a theory.
The advantage of a theory is that it allows for a simplified picture of nature and makes large numbers of difficult experiments unnecessary. Without a theory of gravity, for example, one could imagine one or more journals devoted to the topic of how things fall. Papers would be published describing experiments in which investigators observed the fall of bricks, rocks, oranges, apples, bags filled with various materials, all from different heights, with measurements taken on the speed of descent, force of impact, the effects of climate, altitude , temperature etc. While we might now smile at the absurdity of such experiments, we do so only because we know that Newton’s theory of gravity holds true and makes all these experiments superfluous.
There are examples of this process in biology. Both Darwin and Wallace, and many other biologists before them, collected vast amounts of data about the morphology and comparative anatomy of species. These data now seem boring and trivial when compared to the elegance of the theory of evolution by natural selection that emerged from them. In the 18th and 19th centuries biologists performed hundreds of experiments trying to prove or disprove the idea of spontaneous generation of life. Reams of data were published comparing the growth of “animalcules” in infusions of hay, vs. turnips, vs. potatoes vs. chicken broth and so on. The idea that any organic medium exposed to a source of microorganisms will allow for their growth obviated the need for all these redundant experiments.
It is the theories and ideas that allow for real scientific progress. Of course such theories require experimental data in order to be formulated. But if all we do is collect data, without any effort at theoretical formulation, we may be fooling ourselves that we are learning more about the secrets of life when in fact we are simply generating noise.
(Part 2 will discuss biological theories in more detail, with an emphasis on possible laws of evolution).