The natural science of cosmology
  The network of cosmological tests is tight enough now to show that the relativistic Big Bang cosmology is a good approximation to what happened as the universe expanded and cooled through light element production and evolved to the present. I explain why I reach this conclusion, comment on the varieties of philosophies informing searches for a still better cosmology, and offer an example for further study, the curious tendency of some classes of galaxies to behave as island universes. 
P. J. E. Peebles
astro-ph.CO