  There has been much controversy over weak and strong emergence in physics and
biology. As pointed out by Phil Anderson in many papers, the existence of
broken symmetries is the key to emergence of properties in much of solid state
physics. By carefully distinguishing between dfferent types of symmetry
breaking and tracing the relation between broken symmetries at micro and macro
scales, I demonstrate that the emergence of the properties of semiconductors is
a case of strong emergence. This is due to the existence of quasiparticles such
as phonons. Furthermore time dependent potentials enable downward causation as
in the case of digital computers. Additionally I show that the processes of
evolutionary emergence of living systems is also a case of strong emergence, as
is the emergence of properties of life out of the underlying physics. A useful
result emerges: standard physics theories and the emergent theories arising out
of them are all effective theories that are equally valid
