Hans Driesch was a philosopher and biologist who cloned the first animal, a sea urchin (in the nineteenth century). He was a student of Ernst Haeckel, famous for the phrase "ontogeny recapitulates phylogeny." Driesch's discovery that many parts of the sea urchin embryo were capable of producing a complete animal refuted the theory of "preformation," in which the very first cell alone contained the entire future development of an organism. Preformation suggests that starting with one cell taken from the two-cell - or four-cell - stage, would lead to one-half - or one-quarter - of the organism.
Driesch saw clear evidence of a kind of teleology in the ability of lower organisms to rebuild their lost limbs and other vital parts. He used
Aristotle's term "
entelechy" (loosely translated as "having the final cause in") to describe the organism's capacity to rebuild. Driesch said this disproved the theory of preformation from an original cell. Driesch studied the original cells of a sea urchin, after they had divided into two cells, then four, then eight. At each of these stages, Driesch separated out single cells and found that the separated cells went on to develop into complete organisms (instead of just one-half, or one-quarter, etc. of the organism). His work is regarded as the first example of biological cloning.
C. D. Broad rejected Driesch's idea of entelechy as a non-material, non-spatial agent that is neither energy nor a material substance of a special kind, but we should note that it well describes the information content of any cell that lets it develop into a complete organism. Driesch himself maintained that his entelechy theory was something very different from the substance dualism of older vitalisms. So what was Broad's criticism of Driesch? Neither thinker could produce a clear description of their vital element.
Broad thought vitalism is an
emergent property. He saw that the kind of emergence that leads to water and its unique chemical properties, when compared to the properties of its molecular components hydrogen and oxygen, has no element of purpose or teleology. The emergence of life (and mind) from physics and chemistry, however, clearly introduces a kind of design or purpose. Modern biologists call this
teleonomy, to distinguish it from a metaphysical
telos that pre-exists the organism.
The term teleonomy, which is very close in meaning to entelechy, was introduced by
Colin Pittendrigh in 1958, used by
Jacques Monod in his 1971
Chance and Necessity, and clarified by
Ernst Mayr in his 1974 article
Teleological and Teleonomic: A New Analysis, his 1988 book
Toward a New Philosophy of Biology, and his 1992 article
The Idea of Teleology.
Monod's colleague François Jacob summed it up as "The goal of every cell is to become two cells."
It seems likely that both Driesch and Broad were trying to grasp this teleonomy.
promoted Driesch's ideas tp explain the "directive" and purposive processes in both body and mind as a proposed solution to the
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