If the future is as real as the past, does that mean our choices are predetermined?
Reflections on the epistemology of time and existence.
This question into whether our choices are determined if the future is as real as the past touches profound interlocks of physics, in the matter of entropy especially, with philosophy, and this question, particularly of free will and determinism or time and existence.
Entropy thus is really a measure of our ignorance, not a measure for the actual state of the system. It quantifies which differences between microstates we think aren’t interesting.
- Sabine Hossenfelder, Existential Physics.
In order to look into the nature of entropy and the role it plays in the directional flow of time, it might just be possible to unravel such a tapestry that lies between the physical laws which govern the universe and those philosophical implications of a block universe, where past, present, and future sit on an equal footing.
Entropy is the measure, in terms of thermodynamic, of the extent to which a system is disorderly. The second law of thermodynamics asserts that in an isolated system, entropy will increase overtime, in the direction of inevitable and spontaneous progression from order toward disorder (Hossenfelder, 2022). The principle, too, implies why so many natural processes go one way, and indeed constitutes the very essence of an arrow of time, that is, one-way time flow. So although the most fundamental laws of physics describe motion and energy and are invariant to time-reversal, the systems nonetheless obey the second law in their macroscopic behavior, hence leading to the phenomenally 'forward motion' of time.
As Hossenfelder points out, the universe didn't have this notion of the arrow of time. The arrow of time is more like an emergent phenomenon from the fact that the universe initially found itself in a very ordered state, and this gave it its direction (Hossenfelder, 2022). Therefore, when it began as the extremely ordered state and its progress to higher levels of disorder, time becomes apparent and develops its directional tendency. This means, without this low-entropy beginning, the statistical tendency for entropy to increase does not necessarily lead to an unidirectional perception of time.
Philosophically, what the future is- is just as real as the past; this is aligned with an eternalism concept that in itself is the block universe theory. In this respect, all time points are past, present, and even future, all of equal existence, while the notion of time becomes an illusion in our conscious mind (Lewis, 1986). This would mean that, if the future is indeed as real as the past, it could only be a deterministic universe wherein events that would occur become fixed and immovable. Thus, there are questions concerning free will and human agency.
If one's life is predetermined, is freedom to act still an option, or are they just reenacting what is meant to happen someday?
One way to approach this question is through the study of determinism and the effects of entropy. The second law of thermodynamics opened the door for statistical formulation in the formulation of how systems behave. Though the laws themselves are deterministic, the trend of increasing entropy is a probabilistic one. That is, this statistical nature means that though certain macroscopic behaviors are overwhelmingly likely, they are not absolutely certain. In terms of human choices, it therefore means that though the general direction of entropy places a framework within which decisions are made, there remains a probabilistic uncertainty at the micro level (Hossenfelder, 2022).
Issues like this have been extensively tackled by analytical philosophers. Take the example of David Lewis's counterpart theory: every possible future event is correlated by some counterpart in a different universe; hence, every possible future is real with no determinism to one (Lewis, 1986). That brings the block universe about due to different potential outcomes for each bringing a set of equal realities into existence. From this perspective, the facticity of the future does not rule out free will but places it in a much larger multiverse, where every choice actually occurs in some other universe.
Another philosophical understanding would be Immanuel Kant's contribution, which adds to this interpretation. Kant had posited that time was not a concept derived empirically from experience but rather a necessary a priori condition for the possibility of experience itself (Kant, 1781/1998). If time were indeed the framework within which we structured our experiences, then it could be conceived as being an eternal construct of the metaphysical, not physical. This separation thus permits a regulated experience of time together with philosophical freedom to make choices independent of the determinism entailed by the block universe.
One can in no way underestimate the role of initial conditions in forming the universe's evolution. That extremely low-entropy initial state is what precedes all the subsequent rises of entropy, thereby giving meaning to the arrow of time. It is also the boundary condition that sets certain states to be much more likely than others in this way of constraining the evolution of the universe. However, it doesn't exclude the possibility of other configurations; it tilts the system toward higher states of entropy (Hossenfelder, 2022). For the human choice, this would imply that even though entropy is what determines the entire trajectory of the universe, decisions made by individuals increase local entropy without necessarily being decided by it.
Deterministic consequences of the block universe theory can further be modified with a philosophical concept known as compatibilism. According to compatibilism, free will and determinism cannot exist as mutual exclusives; rather, they can go along quite well with each other (Dennett, 1984). From this point of view, even if the future is just as real as the past, people can still be said to have free will when making decisions in accord with or at odds with predetermination. This means that the block universe does not exclude free will but merely redefine it under the broader ontological platform.
The statistical nature of entropy introduces an element of indeterminacy at the microscopic level, which could go all the way into the macroscopic regime of human choice-making. In principle, the macroscopic arrow of time appears to have a deterministic direction, but what is behind it are probabilities that allow for all those possible outcomes. This probabilistic framework is consistent with the principles of quantum mechanics, where events at the quantum level are fundamentally indeterminate until they are observed (Heisenberg, 1927). Even though human choices are not directly governed by quantum events, the probabilistic nature of entropy brings an element of uncertainty which may be seen to be free space for human will in an otherwise broadly deterministic universe.
According to Hard Determinism, every event that has happened or happening now was necessitated by prior events and conditions along with the laws of nature. Hence, free will has no room for it (Harris, 2012). However, indeterminism will allow for some form of randomness in the universe which may, therefore, be an avenue to ground free will. The second law of thermodynamics, based on statistical underpinnings, occupies an intermediate position by suggesting that the universe trends toward increased entropy, but there is room for probabilistic variations within this trend.
This reconciliation of these physical and philosophical perspectives requires subtlety in understanding the nature of time and causality. If the future is indeed as real as the past, as the block universe theory argues, it is not thereby determined that anything and everything that happens is set to happen in some predestination sense that excludes free will. Instead, it suggests a reality in which all events are equally existent, but our perception and experience of time within this framework permit the subjective experience of making choices. This duality is compatible with the statistical nature of entropy, and it allows the macroscopic, deterministic behavior of a closed system to be accompanied by microscopic probabilistic tendencies as a bridge between the determinism of the fixed block universe and the dynamical nature of human agency.
Thus, applying these concepts, one can notice that the reality at the future point does not imply that it is determined by our choices (if viewed in the context of entropy and the theory of the block universe). It thus creates a rather complex relationship between the trend and the possibility of determination. Entropy provides time with a sense of direction; it defines the behavior of systems universe.
These ideas have long been the kind of subjects that historically speaking- analytical philosophers have been concerned with i.e., in attempting to find some reconciliation between the deterministic nature of physical laws and human experience as per the capacity for choice and agency. Of these two pertinent theories are David Lewis's counterpart theory and Immanuel Kant's transcendental idealism. This sets up the following philosophical insight: based on the principles of entropy and the arrow of time, time itself is as at once an objective dimension and a subjective arena- wherein human agency unfolds.
This premise doesn't imply our choices are determined, therefore, the physics of entropy lends itself naturally to a view that includes both determinism and free will in the broader scheme of the block universe. Philosophical theories add conceptual tools for the better handling of these intricate relationships among time, causality, and human agency. This is a very fertile ground for the interplay of entropy and philosophical thought to understand the nature of time and existence- the truth that- if the future is as real as the past, then it seals nothing irrevocably and does not predetermine anything but situates our choices within a landscape of probabilistic possibilities conditioned by the universe's initial conditions and the inexorable march of entropy.
References
Dennett, D. C. (1984). Elbow Room: The Varieties of Free Will Worth Wanting. MIT Press.
Harris, S. (2012). Free Will. Free Will, Determinism, and Compatibilism. MIT Press.
Hossenfelder, S. (2022). Existential Physics: A Scientist's Guide to Life's Biggest Questions. [Summary of Chapter 3].
Heisenberg, W. (1927). Über den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik. Zeitschrift für Physik, 43(3-4), 172–198.
Kant, I. (1998). Critique of Pure Reason (P. Guyer & A. W. Wood, Trans.). Cambridge University Press. (Original work published 1781).
Lewis, D. (1986). On the Plurality of Worlds. Blackwell Publishing.
Great piece Sanjana! I think about the perception of patterns in behaviour that enables me to make a choice rather than remain at the mercy of my unconscious responses to a situation. Your piece makes me wonder about how the governing principle of karma fits in your hypothesis.