Physical And Chemical Laws
Living organisms form a hierarchy in which each higher level represents a distinctive principle that harnesses the level below it (while being itself irreducible to its lower principles). Accordingly, an organism's phenotype represents a higher level than its genotype, and is reflected by the placement of phenotype above genotype, not at the same level. This difference is possible because part of the genetic code includes instructions for making sensory devices that can detect either chemical, electrical, or mechanical signals. Once a cell builds and deploys sensors, it begins to collect information (that is not genetically encoded) about its environment. This gives it access to periodically updated or continuous signals that allow a primitive sense of time, and memory to develop. By recording such signals and learning to recognize patterns in them that are crucial to survival, living organisms gain access to a type of information that is constrained by, but not derived from, both physical laws and genetic code. In other words, genes determine the types of sensors a cell can make, but genes do not specify the patterns of information a given cell will receive nor the kinds of responses it makes to any given signal. The responses are harnessed by the cell's machinery to useful purposes, survival and reproduction.
With Polanyi's analysis in mind we can construct a provisional hierarchy for living organisms. According to this view, physical and chemical laws are the most fundamental, but alone they are probably not adequate to explain life's processes or its organization. The genetic code, the sequence of a cell's DNA, is placed on a higher level because it is subject to additional constraints layered on top of the physical laws. In addition to following chemical and physical laws (e.g., that govern covalent bonds and weak bonds, molecular stability, folding into a helix, etc.), DNA's structure, its sequence of bases, has been subject to constraints...
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