An example of an analogy employed in popular science writing"
"These elementary structural units of living matter are usually known as 'cells'; they could also be called 'biological atoms' (i.e., 'indivisibles') in the sense that the biological properties of a given type of tissue will be retained only so long as it contains at least one individual cell.
A muscle tissue, for example, which is cut to the size of only half of one cell, would lose all the properties of muscular contractions, and so on, exactly in the same way as a piece of magnesium wire containing only one half of a magnesium atom would no longer be magnesium metal, but rather a small piece of coal."
George Gamow (1961) One, Two, Three…Infinity. Facts and speculations of science, Revised Edition, Dover Publications, Inc., New York.
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This analogy is based upon the explicit idea that a tissue comprising a single cell retains its properties (surely questionable in many cases?), and the implied suggestion that an element sample of a single atom would retain its chemical properties. The latter is a common form of misconception (a 'macro-micro confusion) where it is assumed that bulk properties reflect the properties of the individual atoms or molecules, rather than emerging from large numbers of them interacting.
It is not possible to have a wire of a single atom, and a single atom of magnesium does not have the properties of bulk magnesium And 'half a magnesium atom' may be a carbon atom, but it is not a small piece of carbon (as in graphite, diamond…) and it certainly is not a piece of coal which is not even a form of pure carbon.
Read about the nature of alternative conceptions
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Read about historical scientific conceptions
