Perdurance and the incoherence of B Theory of Time

Overview 

In a previous post, I showed why the A theory of time is the better explanation of our lived experience and why the B theory leads to absurdities.  Here

I wish to elaborate on my previous work, further exposing why B theory is incoherent, in particularly in reference to implications to leading to determinism and it's relation to God.

While perdurance seems to offer some genuine change on their view. However, on closer analysis it amounts to the same issues of arbitraryness of distinction of parts. For instance,  4D worms becoming structured in such a way to be 'carwise' or 'catwise', but this becoming is tenseless and if the proponent of B theory are acting genuinely consistently, they have to accept the real possibility, these 4D blocks exist equally real in all directions, extending possibly infinitely into the future. 

Terms expanded

Perdurance theory holds that, within the 4D block universe of B theory, objects are composed of temporal parts. For example, a banana at a given time slice is merely one "temporal part" of the whole 4D object. According to this view, change is not the passage of time but rather a sequence of these temporal parts existing tenselessly within the spacetime block.

However, this framework faces a critical issue: each temporal slice exists on a tenseless reference frame, with no slice being preferred. Consequently, every part of the banana—unripe, ripe, and overripe—exists simultaneously and equally real in the 4D block.

The Problem of Change

The problem becomes apparent when a B theorist attempts to describe something as simple as the changing ripeness of a banana. The Stanford Encyclopedia of Philosophy describes it like this: 

...the ‘problem of temporary intrinsics’ or sometimes the ‘problem of change’). The banana in the fruitbowl was unripe a few days ago, and today it is overripe. Surely nothing can be both unripe and overripe?  Of course, it’s the fact that the banana is unripe and overripe at different times which saves it from metaphysical peril: we all know that. But it would be nice to understand why this fact is crucial: what is it about the passage of time which makes it possible for one and the same object to have apparently incompatible properties?¹ 

 with the solution being 

If the banana has temporal parts, this explains how it can change: an earlier temporal part of the banana is unripe, while a later temporal part of the banana is overripe. More grandly: an earlier temporal part has the property being-unripe, while a later temporal part has the property being-ripe. There’s no mystery here, any more than there is mystery in your being both hot and cold by having a hot head and cold feet: we’re all familiar with the fact that different parts of the same object can have different properties.¹

The issue being that the authors of the Stanford Encyclopedia of Philosophy states that it isn't really change at all, the 4D block are permanently unripe, ripe or overripe all at the same time. In other words,  commiting to eternalism (B theory of time), believing every reference frame is equally real, this makes real change and the intuitive flow of time illusory. 

Implications and why this leads to determinism. 

If all points are equally real, and just as the past cannot change, the B theory insists the future is fixed and Immutabile by definition. Our intuitions tell us "yes, but we expect bananas, to go unripe to overripe! That's just cause and effect." This misses the point, yes in practical terms, we know bananas do that, but that's assuming A theory of time worldview. 

If We take a different analogy instead, say a hypothetical person. If Perdurance on B theory is true, her past, present and future is equally real, meaning every time slice is already complete. What she will do a week, a year or any point in the later than direction, is already complete,  meaning she couldn’t really have done otherwise. 

If B theory time is true, this applies to everything in the universe, including you and possibly even the universe itself. Take William Lane Craig's words:

On the perdurantist view, persons are not what we normally think them to be: self-conscious individuals who act and react with other things in space and time. Such individuals are, on the perdurantist view, just spatio-temporal parts or stages of persons, which are really four- dimensional objects. As such, persons are not self-conscious and have no intelligence, no volition, no emotions, no interactions, no agency, no moral responsibility, no aesthetic appreciation, indeed, virtually none of the properties we normally associate with persons. Persons, on this view, are four- dimensional objects which are changeless, non-conscious entities.² 

This has drastic implications to genuine freewill and our justice system, that requires we have accountability for our actions. If we couldn't have done otherwise,  we can't be guilty of any crimes or omissions committed, we couldn't have changed our mind, leading to serious questions on salvation. 

How can people freely come to believe in God, if they couldn't have done or changed their mind in any way?

Any theory that commits you to believing all moments in time are real, face this kind of serious objection.  And I seriously ask every reader to think if this is really how reality work?

Metaphysical Assumptions on General and Special Theory’s of Relativity 

Additionally,  even if we accept the general relativity (GR) and special relativity (SR) does not necessarily entail the truth of B theory of time. Relativity, while profoundly influential in shaping our understanding of spacetime, operates as a physical theory that describes the behavior of matter, energy, and spacetime under certain conditions. However, the metaphysical implications we draw from it such as adopting a B-theory view of time go beyond the domain of physics into philosophical interpretation.

1. No Privileged Frame ≠ No Objective Present

GR and SR demonstrate that there is no detectable universal frame of reference for time. However, this does not eliminate the possibility of an objectively privileged "now" that exists beyond our observational capabilities. A neo-Lorentzian interpretation, for example, posits an undetectable absolute time, consistent with the A theory, even if it cannot be empirically verified.

2. Relativity Describes Relations, Not Ontology

Relativity provides models and mathematical frameworks to explain relationships between events in spacetime. While these models are incredibly successful, they do not inherently dictate whether the past, present, and future are equally real (as in B theory) or whether only the present is real (as in A theory). The metaphysical status of temporal ontology remains underdetermined by the physics.

3. Flow of Time and Experiential Reality

The experience of time flowing and the division of time into past, present, and future is an undeniable aspect of human experience. While relativity shows how perceptions of simultaneity vary between observers, it does not prove that this flow is illusory or that distinctions between past, present, and future are meaningless.

4. A Theory Remains Consistent with Relativity

The A theory of time, especially in its neo-Lorentzian form, is compatible with relativity in practice. The absence of an empirically detectable "now" in relativity doesn't preclude its existence. Instead, it suggests that "now" operates outside the scope of relativity's framework.

5. Metaphysical Assumptions of B Theory

The claim that the past, present, and future are equally real is not a physical necessity derived from relativity but a metaphysical stance. B theory extends the implications of relativity to assert that time is a dimension like space, leading to the block universe. However, this is an interpretation rather than a direct consequence of the physical theory.

Conclusion

I believe I have shown that B theory is incompatible with our lived experience and genuine freewill, making it absurd to live consistently.  

References

1.https://plato.stanford.edu/entries/temporal-parts/#ChanTempPart

2.William Lane Craig, Crossway Books, Time and Eternity: God's relationship with time, 2001, page 205 e-book edition.