We humans provide the most complicated example that we know of so far
Out of the fundamental force fields described by our physical theories, more and more elaborate structures have grown in the universe that we know, including atoms, molecules, and biological structures such as neural networks, as well as larger structures of planets, stars, galaxies, and galaxy clusters and networks. The weak and strong nuclear forces and electromagnetic forces account for rapid changes in those structures, and the gravitational force accounts for most of the longer-term stability of the larger structures.
Decision-making structures are branching structures that constrain interactions of the fundamental forces — that is, structures that restrict such interactions into finite sets of discrete alternatives — what we describe as “choices”. The most subtle ways in which such choices are actually resolved — what we call “decisions” — are described by our theories of quantum phenomena, but at the scale of our individual human existence, decisions are just somehow ultimately made. Some decisions — like the outcome of rolling dice — are random, as far as we can understand their causes, but others — like our decisions to roll dice — are deliberate, again as far as we can understand their causes.
