There are advocates for simple determinism who would assert that everything we do is predetermined and therefore our apparent choices are really an illusion. From that point of view, we don’t have any choices and all the outcomes that appear to follow from such imaginary choices are predetermined and beyond our ability to influence. In short, the chain of causality that began in the distant past, perhaps with the origin of the universe, set in motion a chain of cause and effects that still continues and will continue into the future. That chain of causality passes through us and determines what we think and do. I think this view takes all meaning from existence and makes life largely pointless, which doesn’t necessarily make it wrong. However, I reject it on existential grounds and advocate for a view based on complex determinism.
Before going into complex determinism, let me say something about free will. The free will counterpart to simple determinism is absolute free will (a.k.a. indeterminism), which means one can by choice affect an outcome that is not predictable from its antecedents. In short, one can do things that violate the principle of causality (a.k.a. magic). For example, I used to challenge advocates of this position to go to the roof of the building and walk across the open space over the street to the roof of the building on the other side. To do this would both violate the principle of causality and demonstrate affecting an outcome by choice that is not predictable from its antecedents. I’ve never had an advocate for absolute free will take me up on this opportunity to demonstrate the validity of their position. However, just as there is an alternate form of determinism there is an alternate conception of free will, which I’ll come to shortly.
The libertarian philosopher Richard Taylor proposed that the way out of the dilemma posed by simple determinism is to recognize human-agency as a primary factor in causation. That is human-agency can alter a chain of causality passing through one and initiate a new branch in an unfolding sequence. This brings us back to free will. In this view, free will is no longer absolute but rather is probabilistic. Complexity theory suggests that in any given situation there are usually multiple possible outcomes, none of which require magic to be effected. Each of these possible outcomes is more or less probable than another. The most common outcome is the one with the highest probability. This is what is sometimes described by the phrase “the path of least resistance.”
However, human-agency through intention and deliberate choice, based on forethought and anticipation of consequences, can influence and change the probability functions of potential outcomes. When I was a professor, I often talked about behavior in terms of what I refer to as the three-legged stool (biological causes, environmental causes and self-agency). It is this latter concept that lies at the root of the notion of the “cooperative alliance” in behavioral intervention that I discuss in a paper on behavior and quantum physics. In short, it is unlikely that one will affect a significant and lasting change in behavior without the active cooperation and collaboration of the subject with the change agent.
As a side bar, I would add that most, if not all, human religions presuppose that the underlying nature of reality is indeterminate and magical (e.g., witness the use of prayer in an effort to produce and outcome that cannot be predicted from the antecedents, i.e., appeals for divine intervention are in effect based on a belief in indeterminism or magic). Herein lies the source of my skepticism about religious claims. As for the existence of God, I can only say that depends on how one defines the nature of God. I see absolutely no basis for an anthropomorphic God and view such depictions as the artifact of a paucity of imagination. If one wants to define God as the ground state from which our universe arose then I can accept that as a possibility whether called God, Quantum Field or by some other name. What the characteristics of such a ground state might be is an open question and might include some of the claims of mystics and other spiritual explorers.
In my view, we do have the ability to make real choices. We can make choices, at least, from among those potential outcomes that are possible given the antecedents. Our choices, reflected in our intention and actions, influence (but do not control) the probable outcomes available in situations in which we are actors. I also think that most of us, most of the time fail to exercise self-agency and simply follow the path of least resistance.