One of the more contentious debates in the philisophy of physics is whether free will can exist, or if all actions, and indeed all behaviors including human decision making, are strictly the results of physical processes, and therefore devoid of any true free will.  This article presents a line of reasoning that suggests that free will can and does exist.

As a starting point, we first must recognize the potential for randomness.  Here are two thought experiments that require true randomness to be possible:

  1. Imagine a perfectly uniform material composed of many identical particles that are bound together with a non-infinite force.  Now imagine applying perfectly balanced equal but opposite forces of attraction on the material that sufficiently exceeds the individual bonds between the particles.  At some point, given high enough equal but opposite force, the material must split apart at one or more points.  Since our material has equal force of bonds between particles, and our equal but opposite forces acting to pull the material apart are perfectly balanced, there can be no preferred point at which the material will break.  As such, the point or points of breakage must be random.
  2. Imagine two perfectly identical subatomic particles possessing mass travelling in equal but opposite directions precisely towards each other with high momentum.  We specify as a precondition that the two particles are fundamentally indivisible particles.  At the point when these particles meet each other, they cannot simply stop or else we would violate the law of conservation of energy.  We also set as a precondition that the particles are inelastic.  Since the particles are indivisible and inelastic, and since they cannot simply destroy energy, the particles must undergo a change of direction that is random.

Myriad scenarios may be imagined.  Given a large enough incidence of potential events at a small enough scale, the probability of the existence of such interactions will aproach 1.  As such, randomness must exist in nature.

Having established a motivation for believing that randomness exists in nature, we move to the question of whether predetermination of a choice of outcome is possible.  To do so, we will posit that such random interactions are possible at the individual level of a particle or a uniform collection of particles, such that ever larger and more complex equal outcome situations are also possible.  At some scale, an entity involved in an equal outcome experiment may be sufficiently complex to be capable of contemplating a preferred behavior in the absence of a-priori knowledge of what event will occur.  For example, let us suppose that in our collision scenario, each of the bodies that will collide carries a color that is either red or blue, and those colors are identical, but each body does not know it’s own color.  Can one of the bodies pre-decide that in the case of a collision, it will move towards the right if the oncoming body is red and it will move towards the left if the oncoming body is blue? The body does not know its own color and yet has predetermiend a choice amongst events that we otherwise have demonstrated must be random.  Since the choice precedes and yet is unrelated to the phytsical event, we therefore can say that in the case of random events free will can exist.

While this series of comclusions carries mathematical appeal, it does little to establish whether free will can exist at a scale of interest to a satisfying level of human exertion of our concept of free will.  After all, to this point we have limited our thinking to scenarios requiring precise equalities in order to establish randomness and choice.  In order to be truly meaningful at a human level, we must consider whether we can now relax our requirement of equality of circumstances while retaining the concept of choice.  We do this by first introducing two additional concepts:  time and approximation of randomness.  Given a scenario of approximate but not perfectly equal physical choices that require non-zero time, can choice cause an outcome that would differ from the outcome if only the minor inequality of circumstances dictated the result.  In our colliding bodies example, let us now reconsider  our body that has decided to move towards the right upon collision with an identical red body.  We shall now specify that in the time from perception of the color of the oncoming body to collision, that our deciding body cannot fully assess whether or not the oncoming body is indeed identical to itself.  In this revised scenario, our deciding body approximates a belief that the two boidies are identical (even though we have now specified that they are not quite identical), and therefore chooses a direction towards which to move at point of collision.  Our key question reated becomes, can the choice itself exert greater influence than the very small variation from perfect equality between the bodies?   It is here where sufficient time for perception being non-zero suggests that the answer is yes.  Therefore, at this point we established these concepts in succession:

  1. Existence of randomness
  2. Existence of predetermination of choice
  3. Existence of time for the perception of the circumstance posited by the choice
  4. Inability to discern if randomness would be necessary
  5. Time to begin to assert the choice PRIOR to the point wherein the non-necessity of randomness would be revealed (the point of collision after perception time has passed.)

What we have shown then is a progression whereby sufficient approximation of randomness (opportunity for choice) is all that is necessary for actual choice to occur.  Since the degree of approximation of randomness is related to perception, then bodies with progressively less granular perceptions may make choices in scenarios of progressively less physical need of randomness.

The only variables, then, that determines choice are the time available and the altering reactions necessary to overcome the reaction that would be dictated by purely physical processes of an event (either random if equality is perfect or precisely defined if equality is imperfect).  In other words, if the time available after perception is sufficient to allow a body to effect a change in circumstances that would avoid the natural physical reaction, then choice or free will can be exerted.

Some philosophers would argue at this point that the decision of what choice should be made is itself predetermined by the composite of all physical processes that have happened previously.  However, in building up our series of circumstances, recall that we began from a state of perfectly identical bodies.  To have been perfectly identical, there can have been no “memory” or “effect” that differed between them.   Furthermore, it is a trivial matter to specify that these were the first two such events ever to have occurred, and therefore no prehistory must exist for the scenario to play out.  Since no prehistory must exist, then the influence of prehistory cannot be credited with influencing the choice made. Instead, the only necessary conditions are perception of randomness, which is really perception of choice, and sufficient time for choice to be exerted.

This is what we herein then describe as the existence of free will.