Outline of a theory of cellular heterogeneity ( cell biology / theoretical biology )

In the effort to advance toward a theory of cellular function that is not completely mechanistic, I have encountered a variable whose significance is often overlooked. This is the degree of heterogeneity of organic tissue, which may vary from highly homogeneous conditions to quite large degrees of heterogeneity, primarily with respect to chemical bonding. For several decades, I have dealt with the theoretical analysis of this type of problem, and here I give a condensed outline of the conceptual changes to which such an analysis is likely to lead. I believe the time is ripe to compare these theoretical arguments with observations. The data that occasion this note are those of Rubin [Rubin, H. (1984) Proc. Nati. Acad. Sci. USA 81, 5121-5125]; they and numerous similar observations suggest the possibility of an advance toward a nonreductionist model of cellular function along lines that are here indicated; the theoretical model is thought of as operating entirely within the framework of quantum mechanics. This paper forms part of a long-extended effort at applying epistemological analysis to biological subject matter. This type of analysis, introduced into physics a century ago by Ernst Mach, has been eminently successful there: One can say with certainty that the two great theoretical edifices that dominate modern physics, the theory of relativity and quantum mechanics, could not have come into existence without thorough epistemological analysis preceding them. The idea that a similar analysis can be applied to matters biological is natural; it has preoccupied me for several decades (1-3; also 4-6). Obviously, the concepts to which epistemological analysis is to be applied are different in biology from what they are in physics. Here, to show the use and meaning of such analysis, I introduce a particularly significant type of concept, namely, the pair homogeneity-heterogeneity. This is occasioned by comparison with Rubin's experimental results about the heterogeneity of cancer cells (7). There are good reasons to suspect that heterogeneity (i.e., variability within any given set of samples) is an essential characteristic of organic life. This idea differs widely from the traditional view that heterogeneity is only a nuisance that is to be circumvented or otherwise eliminated. Hence, controversies and mutual misunderstandings of two groups adhering to these diametrically opposed viewpoints are just