how can navigate if our desire is for absolute truth...
Ruby, my thinking of cells, in regards to the modularity topic, was of them being the basic units of the larger whole. However, it is certainly feasible to look at cells as a larger whole, made up of cellular components, nucleus, organelles, membranes, etc. So in this sense I agree that the "modularity" can go both ways. So I stand corrected.
However, I don't think this has anything to do with your larger point--that of absolute truth. Scientists don't claim anything to be absolutely true. All truth (with only one or two exceptions) is provisional. Where scientists land in the metabolism vs replication vs it's-a-bad-question debate has nothing to do with absolutes.
aha - thanks four comments
re your point here
However, I don't think this has anything to do with your larger point--that of absolute truth. Scientists don't claimanything to be absolutely true. All truth (with only one or two exceptions) is provisional. Where scientists land in the metabolism vs replication vs it's-a-bad-question debate has nothing to do with absolutes.
where scientists land in the debate probably does not have anything to do with the question of absolute truth as such but the fact of having to overlap boundaries reminds scientists of what they may be ignorant of in another field. For example Nick Lane is faced with having to construct a mini reactor to support his proton/leaky membrance thesis.
Kurt Richardson makes this point and this is also a reminder for us not to dismiss those who may have a leaning towards chemistry as barmy simply because we assume we know there is all to know after reading one paper and because the individual may have had some mental health issues. In fact some of the best thinkers have had mental health issues in their private lives
Chemists, for example, provide a description of reality at
the molecular and molecular-complex level. Physics traditionally sits below chemistry as
being the more fundamental science considering the constituents of molecules, namely,
atoms, quarks and maybe superstrings; chemistry supposedly emerges from physics.
However, there is a lot more physics in chemistry than physicists actually know about. The
ability to bootstrap from physics to chemistry is well beyond current science. The problem
is compounded further if we try to bootstrap from chemistry to biology, which deals with
cells and multi-cellular entities. As Douglas Hofstadter  remarks in Go¨del, Escher,
Bach “a bootstrap from simple molecules to entire cells is almost beyond one’s power to imagine”
However, in the paper above Kurt Richardson argues that it is possible for scientists to aim for a substantial realism rather than absolute truth although it would be great to discover universal laws for everything - here in each science discipline one would need to keep in mind the provisional nature of scientific knowledge yet still be open to new ideas and input from neighbouring hard sciences.
aiming for substantial realism rather than absolute truth may help us in our journey too and keep us from ridiculing what in reality we are ignorant of.