A Tension Worth Facing Honestly
If you talk to someone who believes in the Block Universe (Eternalism), they will usually agree that the past, present, and future all exist at once in a giant, unchangeable 4D block.
But when you ask them how they square that with everyday striving, many reach for a workaround. It sounds something like this:
Here is why I think this sits in deep tension with itself. To be clear up front: this is the incompatibilist line of thought. Compatibilists argue that meaningful choice and responsibility can survive even in a fully determined universe, and I address that view at the end. What follows is the case for thinking the two are hard to hold together.
The Three Problems
1. Smuggling Free Will into a Frozen Reality
They are acting as if being good and working hard right now is a dynamic choice they are making, which will "secure" their spot in the good part of the block. But in a Block Universe, you don't get to decide the path at any point. The feeling of "working hard" or "choosing to be smart" is just another frozen slice of spacetime. You didn't write the script; you are just a character playing out the exact geometry of the block.
One distinction has to be made carefully here, because it is easy to slur past. The Block Universe says future events exist. It does not, by itself, say they are necessitated by the present. Those are two different claims: eternalism is about which times are real, determinism is about whether the present plus the laws fix what follows. A block can, in principle, contain genuinely undetermined events—outcomes that simply sit there without having been forced by anything earlier. So the sharp worry is not "the future exists." It is "the future is both already real and already fixed." If you grant both, then your effort today cannot change what that future turns out to be; it is one settled link in a settled structure. (A compatibilist would push back even then, arguing your effort still counts as a genuine cause within the block. The incompatibilist reply is that being a fixed link in a fixed chain is not the same as authoring an open outcome.)
2. You Can't Have It Both Ways
People want to accept the math of a Block Universe because they think it sounds elegant, but they refuse to accept the personal consequences of it. They want to take credit for their successes. You cannot claim the universe is totally predetermined, but then claim you authored the good parts through your own grit.
A static universe has no authors, only observers. If you are part of a completed 4D crystal, you are not creating your future. You are reading it. The "hard work" you do is just information about how the block is structured, not an action that shapes it.
3. Why They Do It Anyway
Human brains are wired for cause and effect. It is existentially terrifying to accept that your struggles, your morality, and your achievements are just static coordinates in a 4D crystal that you have zero control over. So, they invent a psychological safety net.
They "intellectually" accept the Block Universe, but they live as if the future is unwritten. They make plans. They set goals. They take pride in their work. A compatibilist would say there is no conflict here at all. The incompatibilist reading, which this page favors, is that there is at least a real gap between the stated belief and the lived one.
The Reality Check
Why I Think Real Agency Needs an Open Future
If you want your hard work to physically cause a better future in the strong, authoring sense, it is hard to see how a Block Universe delivers that. On the incompatibilist view defended here, that kind of agency requires a reality where the future truly has not happened yet—an evolving timeline and an Absolute Now, where the universe is being built in the present moment.
It is tempting to state this as a clean either/or: either the future is unwritten and your actions shape it, or it is already there and nothing you do matters. But that dichotomy moves too fast. A future that is already real is not automatically a future that is already settled—some philosophers (Howard Stein among them) argue that even a four-dimensional block can leave the future genuinely open. So the honest version of the worry is narrower: if the future is real and fixed in advance, then authoring it in the strong, libertarian sense becomes very hard to make sense of. That narrower claim is the one this page is prepared to defend.
The people who claim to hold both views may think they have reconciled them, but I do not find that reconciliation convincing.
The Deeper Issue
This is not really about physics. It is about how far we follow an interpretation to its consequences. The Block Universe is a perfectly valid interpretation of certain mathematical formulations of relativity. The claim here is narrower than a proof: if you read it the incompatibilist way, it is hard to also treat the future as something you author, since it is already part of the completed geometry of spacetime.
Some physicists and philosophers embrace that conclusion. Others reconcile agency with it. But many people do not live as if the future were fixed. On an incompatibilist reading of Eternalism, the idea that you are the ultimate author of your own future is very hard to make sense of. (Compatibilists disagree; they hold that authorship of that kind was never what agency required.)
So the question becomes: is the Block Universe true, or can we find an interpretation of physics that preserves both the tested predictions of relativity and the possibility of genuine agency?
That is what NeoLET proposes. A real present. An open future. And a universe where your choices matter because the future is not already decided.