RNA (200px)
DNA (200px)
Structures of RNA and DNA: what some have labeled as a "living molecule" or the "secret of life" as James Watson described DNA.
In hmolscience, living molecule, in contrast to a dead molecule, is a hypothetical type of molecule that is said be alive or possess the properties of life. The term arises in discussions on the question of the origin of life, in the spectrum of development between the formation of the hydrogen and the human, in which molecular structures such as DNA or viruses are said to be alive.

Plastidule theory
In 1862, German biologist-zoologist Ernst Haeckel first began to lecture on the origin of species and four years later, in his General Morphology (1866), introduced the terms: ‘Plastide’, ‘Plasson’, and ‘Plastidul’, from the Greek plastikos, from plassein to mold or form, as his designation of the first single-celled organisms, creatures of the lowest morphological order of ‘individual’, as his solution to the origin of life problem.

The creatures or entities themselves Haeckel called ‘Plastiden’, which he considered to be the building blocks from which all life is made, were hypothesized to be filled with a homogeneous substance called ‘Plasson’, which in turn was composed of molecules called ‘Plastidule’ (plural) or ‘Plastidul’ (singular), which were special types of molecules that had the ability to reproduce through a sort of molecular ‘memory’; a conception vaguely said to be similar to or precursory in conception to the way in which the modern view of chromosomes and DNA (molecules) facilitate or rather transmit traits in the process of reproduction. [4] The term ‘Plastidule’ tends to be rendered in the modern as the "first living molecules"—although this may not exactly be a correct translation, as Haeckel seems to have held a monism viewpoint in his mind

Biogen hypothesis
In 1903, German physiologist Max Verworn proposed the term “biogen” as a kind of living molecule that is constantly modified by chemical processes within the protoplasm. [5] In 1913, British biochemist Frederick Hopkins commented on vagueness associated with the biogen/living molecule premise: [6]

“It is clear that a special feature of the living cell is the organization of chemical events within it. So long as we are content to conceive all happenings as occurring with a biogen or living molecule all directive power can be attributed in some vague sense to its quite special properties. But the last fifteen years have seen grow up a doctrine of a quite different sort. I mean the conception that each chemical reaction with the cell is directed and controlled by a specific catalyst [enzyme]. We make a real step forward when we escape from the vagueness which attaches to the ‘bioplasmic molecule’ considered as the seat of change.”

Here we may compare British animal psychologist Lloyd Morgan's 1929 biocule concept.
living molecule (2013)
An artistic conception of a living molecule, or what looks like a protein molecule touched by the hand of god, in a 2013 article discussing the history human molecular formulas, e.g. Thims human molecular formula (2002). [8]

Semiliving molecule
An early January 1957 Manhattan meeting for the American Association for the Advancement of Science, debated what seems to be English biochemist John Haldane’s 1929 reducing atmosphere / hot thin soup origin of life theory of—which holds “that The first living or half-living things were probably large molecules synthesized under the influence of the sun’s radiation”. This debate spurred the Time magazine article “Of Molecules & Men”, which speculated on this further, discussing concepts such as “semiliving molecules” and automation. [7] The premise of a "semi-living molecule", i.e. a molecule that is so-to-say "half-alive", in defunct theory of life (2009) retrospect, is a near-absurdity, but one difficult to discern in conceptual context.

The term living molecule is a near-synonym to living being, living matter, living organism, or living system. Nanotechnology examples might include the “walking molecule” (2005) or “molecular carriers” (2007), i.e. molecules designed to carry load, akin to little workers. In a rigorous view, the term "living molecule", to note, as in a molecule (any molecule) being alive, is an unfounded theory.

In 1903, religious writer Effie Shirey devoted a chapter to molecules, in which she argues that “all forms of created life are evolved from a molecule”, such that living molecules have tiny sparks of electrical force, in an attempt to unify Christianity, evolution, and science, in a novice way. [3]

In the 1997 book The Evolution of Love, Ada Lampert, evolutionary psychology professor at the Ruppin Institute of Israel, uses the concept of “living molecule” in her attempt to trace the origin of love backwards into the decent of evolution, in the context of matter. The following is her spin on this logic:

“Just as the atom was created, and the molecule and the earth and the water above it, so life appeared governed by the same processes and the same laws, constituting elementary particles in a stable, close-knit group. The living molecule appeared 4 billion years ago, and to this day, it is one and the same—so-called DNA (deoxyribonucleic acid). Life, as far as we know, appeared only once, and the entire rich variety of life forms is the metamorphosis, the evolution, of this molecule.”

Then she asks: how does life differ from inanimate matter? To which she answers:

“[Life differs from inanimate matter] by the inner structure of the molecule, a structure that has far-reaching implications. The uniqueness of this molecular structure, as opposed to any other molecule, lies in the fact that its borders are made of meticulous connoisseurs, also close-knit groups of particles, who inspect potential partners and choose only those whose addition to their group will recreate or replicate themselves. Replication of the existing molecular structure by the joining together of identical raw materials, wandering around in nearby space, is the very essence of the phenomenon called life. The DNA molecule is ‘alive’ because it replicates itself and thus creates new life, reproducing offspring.”

This logic, however, is incorrect, as discussed below.

Difficulty on term
This argument, however cogent it may look superficially, is incorrect. If one looks at the life criterion definitions (and their disproofs) and assigns molecular formulas for each structure, as done on the evolution timeline, the idea of a certain number of molecules being alive (five in case of DNA) becomes an unfounded concept hinging on the suppositions of perpetual motion.

In other words, in the context of the evolution timeline, which shows the steps in the synthesis from smaller to larger, the proposition of an intermediate step such as DNA being alive, assumes that its precursors must also be alive, which leads to the conclusion that the hydrogen atom must be alive. This conclusion, however, makes no logical sense. [2]

1. (a) Lampert, Ada. (1997). The Evolution of Love (pg. 6). Greenwood Publishing.
(b) Ada Lampert (author bio) – Greenwood Publishing Group.
2. Thims, Libb. (2009). “Letter: Life a Defunct Scientific Theory”, Journal of Human Thermodynamics, Vol. 5, pgs. 20-21.
3. Shirey, Effie M. (1903). The Angel’s Diary (ch. V. A Treatise on Molecules, pg. 216). The Merchants Pub. Co.
4. Jacobensen, Eric P. (2005). From Cosmology to Ecology: the Monist World-View in Germany from 1770 to 1930 (pg. 106). Peter Lang.
5. Staff. (1903). “The Living Substance: a Theory: Die Biogen-Hypothese”, Nature, 67: 385-86, Feb. 26.
6. Ball, Philip. (2011). Unnatural: the Heretical Idea of Making People (pg. 133). Vintage Books.
7. Staff. (1957). “Science: Of Molecules & Men”, Time, Jan 07.
8. Anon. (2013). “Fórmula química del ser humano” (Chemical Formula of Human), Triplenlace Quimica, Sep 4.

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