[madbadgalaxyman (Robert)]

I agree with you, Craig, that for us, as human minds, empirically tested and self-consistent physical models, (which in my view must also incorporate the postulates of causality and the conservation of mass/energy in order to make sense), are the closest thing that we can get to an accurate description of the world.

But beware of theorists and their computer models......for years, theorists were trying to "make" massive stars in their computers, and the stars just wouldn't form in these simulations, due to the many barriers that exist to gravitational contraction, e.g. magnetic fields, photon pressure, angular momentum, etc.
Yet obviously, nature has no trouble making massive stars!!
Yes, the computer models didn't work......so astronomers who study massive star formation are waiting for observations of sufficient angular resolution in order to be able to see how the task is accomplished in the real world.

Similarly, it must be possible that those cosmological simulations that can replicate the observed pattern of the "large-scale structures" in the universe (such as voids, walls, shells, etc.) are missing something.
Ostriker, for instance, suggested a large number of small "mini bangs" to clear matter out of the voids, and to make galaxies form only on the walls of the voids (as they have done!).

In relation to the dark matter idea, which I regard as proven, at least at the level of certainty that constitutes proof in science, I can sometimes understand why people are looking for other factors that might cause the ongoing structure formation in the universe......in a recent informal study of some supercluster structures, I found many galaxies that sit by themselves in splendid isolation, with perhaps only one or two small companions;
so the question that suggests itself is: how can anything form at all, given the ultra-low mass density of some of these regions of space? (dial "DM" for dark matter ?)