One of the biggest intellectual potholes in thinking about the origins of life is the idea of irreducible complexity.
This is the conceit that that there's no way a complex system like, for example, the mammalian hormone, aka endocrine, system, could have evolved through natural selection.
No-one has contributed more to bolstering this idea than, ironically, one of the leading scientists in the history of astrobiology: British astrophysicist Sir Fred Hoyle.
In the 1950's Hoyle was the scientific creative free-thinker who led us to the discovery that most of the elements of the Periodic Table are forged in stars. That we in our carbon, nitrogen, iron-selves, are thus star stuff; the descendants of stars.
But towards the end of a remarkable and fiery scientific career, Hoyle came to believe that life's complexity was just too great to be explained by natural selection. There must be some Intelligent force at work, thought Hoyle, some cosmic clockmaker.
In 1981, Hoyle argued that the natural emergence of even the simplest cell was akin to the likelihood that "a tornado sweeping through a junk yard might assemble a Boeing 747 from the materials therein."
(He first made the argument, ironically, in an invited talk given to students at the California Institute of Technology--an institution founded by George Ellery Hale.)
With this jumbo jet analogy, Hoyle gave the emerging Intelligent Design community one of its central motifs.
Hoyle was famously willing to be wrong, and in this he was both wrong--and, as he usually was--helpful to the larger scientific conversation in his willingness to argue energetically and thoughtfully. (Hoyle also coined the term "Big Bang", though to argue that it didn't occur.)
Because Hoyle's argument for irreducible complexity forces us to look at it for what it is: an oxymoron.
All biological complexity, by its very nature, arises from simplicity.
Indeed, he'd been the first to reveal this showing how the complexity and order of the 94 naturally occurring elements of the Period Table emerge from the nuclear reactions inside stars. Hoyle helped show that stars are the initial engines of biological diversity.
All of the key biomolecules, the molecules of life are, peptides: they are chains of simpler building blocks.
Thus even the most complex proteins, such as the magnificent, huge folded protein hemoglobin--the Uber-molecule for oxygen transportation in our bodies--is the bulk product of 574 individual relatively simple amino acids.
Ditto for DNA--a chain of just four so-called DNA bases--and starches, varied and complex chains of the simple sugars glucose and fructose.
As Cambridge University biochemist and origins of life researcher John Sutherland has noted, "Complexity is in the eye of the beholder". (After a decade of trying different recipes, Sutherland was able to synthesize one of the four nucleotides that make up RNA.)
I didn't think of it until writing Sutherland's quote that perhaps it's a particularly clever riff on that other icon of seeming irreducible complexity, the human eye.
As so often in the search for the origin of life, how we see the question ultimately reflects how we see ourselves.
(My eye from a recent optometrist appointment!)