  Some properties of the world are fixed by physics derived from mathematical
symmetries, while others are selected from an ensemble of possibilities.
Several successes and failures of ``anthropic'' reasoning in this context are
reviewed in the light of recent developments in astrobiology, cosmology and
unification physics. Specific issues raised include our spacetime location
(including the reason for the present age of the universe), the timescale of
biological evolution, the tuning of global cosmological parameters, and the
origin of the Large Numbers of astrophysics and the parameters of the Standard
Model. Out of the twenty parameters of the Standard Model, the basic behavior
and structures of the world (nucleons, nuclei, atoms, molecules, planets,
stars, galaxies) depend mainly on five of them: $m_e,m_u,m_d,\alpha,$ and
$\alpha_G$ (where $m_{proton}$ and $\alpha_{QCD}$ are taken as defined
quantities). Three of these appear to be independent in the context of Grand
Unified Theories (that is, not fixed by any known symmetry) and at the same
time have values within a very narrow window which provides for stable nucleons
and nuclei and abundant carbon. The conjecture is made that the two light quark
masses and one coupling constant are ultimately determined even in the ``Final
Theory'' by a choice from a large or continuous ensemble, and the prediction is
offered that the correct unification scheme will not allow calculation of
$(m_d-m_u)/m_{proton}$ from first principles alone.
