# Newcomb's Paradox **URL:** \ **Category:** Logic & Philosophy of Mathematics\ **Created:** [March 11, 2026, 3:09am UTC](https://www.thephilosophyforum.com/t/newcombs-paradox/298 "2026-03-11T03:09:32Z")\ **Posts on this page:** 1\ **Showing post:** 392
**Author:** ![AlveK](https://yyz1.discourse-cdn.com/flex007/user_avatar/www.thephilosophyforum.com/alvek/32/594_2.png) [@AlveK](https://www.thephilosophyforum.com/u/AlveK)\ **Post date:** [March 14, 2026, 6:08pm UTC](https://www.thephilosophyforum.com/t/newcombs-paradox/298/392 "2026-03-14T18:08:15Z")
## What is P-Determination? > [@Pierre-Normand](#): > > The issue is not with the relata but with the shape of the relation you’re asking me to specify. Your earlier quote heavily suggested it was the eventhood of the relata itself that was the issue. But fine, I will roll with your rolling definition. I will adjust to your latest reply. **My attempt at formalizing your relation, this _P-determines_, has the wrong “shape”.** What do you mean by that? Let’s see. > [@Pierre-Normand](#): > > You ask me to fill in the blanks: “Thing 1 P-determines Thing 2.” But this already imports the structure I’m resisting: a binary relation between two events, one of which determines the other. Okay, so there are four properties of my earlier suggestion for _P-determines_ that are being mentioned here, and _any_ combination of them may be at fault. So, here they are: 1. _P-determines_ is a relation. 2. _P-determines_ is binary (it takes two arguments/inputs) 3. _P-determines_ is a kind of determination 4. _P-determines_ takes events as its arguments/inputs Let’s look at each property. Is _P-determines_ a relation, in your view? > [@Pierre-Normand](#): > > Your ontic and epistemic categories share an unstated presupposition: that the basic relata of determination are events, … You talk of “the relata of determination”, though you only object to them being events in that quote. Okay, so _determination_ is something that has relata. What is a relatum? [_A thing that is related._](https://www.merriam-webster.com/dictionary/relatum) If you talk of the relata of some thing, denoted as R for example, then you are saying R has a relata… you are saying R is a relation. If you are making a predicate logic, you’d say R is a predicate with more than one argument. So, “determines” is a relation. We say _X determines Y_, making X and Y the relata of the determination relation. Now, _P-determines_ is a **kind** of determination, obviously. You have been saying all this time that there is some kind of determination between one’s action to TB/OB, and the contents of Box 2. If there was no determination whatsoever, then it’d be irrelevant, no? And to quote you, just in case you’ve forgotten your own stance, here it is: > [@Pierre-Normand](#): > > So the determination is neither merely epistemic (“sad news”) nor “ontically retrocausal.” **It is the distinctive determination** that practical knowledge has with respect to what it understands. (bold by me) > [@Pierre-Normand](#): > > It is a practical determination (…) So, this determination of yours, what we are calling _P-determines_, short for both _Pierre determines_ and _practically determines_… it is a kind of determination, and therefore a relation, by the above argument. It relates things, whatever those things are. Those things may not be events or even tangible, but they are relata nonetheless. So, we uphold the first claim above. The first claim cannot logically be the claim you are rejecting regarding _P-determines_. Let’s move on to the second. 1. _P-determines_ is binary (it takes two arguments/inputs) Well, since we know _P-determines_ is a relation now, this reduces to the question: is _P-determines_ a binary relation? Well, let’s check the textual source here. > [@Pierre-Normand](#): > > > [@Suny](#): > > > > This still doesn’t matter and CDT is right. Even if the predictor predicts the reasoning process that will happen in the room, you picking one box or two still doesn’t change the content of the box in front of you. > > It doesn’t _change_ the content _from_ what it was when you entered the room. But it does _determine_ what this content is (and was). So here, you are saying that Thing 1 _determines_ Thing 2. Specifically: [Picking one box] _determines_ [Content of Box 2] I don’t see any other relata here, and my arithmetic may be lacking here, but I count _one… two!_ Two relata for you determination relation. Now of course, maybe the above relation is that of **mere epistemic determination,** but you have already agreed that this is not sufficient alone. So if your response to Suny here had any chance of being relevant, it was because you were specifically talking about _P-determination._ So, steel-manning your position, you were saying this: [Picking one box] _P-determines_ [Content of Box 2] Therefore, _P-determines_ is not just a relation, it is a binary relation. So, let’s move on. 1. _P-determines_ is a kind of determination Now, this one is pretty easy. Several of my quotes above establish this is meant to be a kind of determination. Also, if it isn’t a determination, how would it be relevant? 1. _P-determines_ takes events as its arguments/inputs This one is tricky. You have both seemingly taken issue with this holding between events, but you have also said that isn’t really the issue. However, it seems like I have ruled out the other options, so what else could be the problem than this? **You say I have gotten the shape of _P-determines_ wrong… okay, then map out the shape, please. Explain rigorously, clearly, logically: what this _P-determines_ is, and what it holds, or does not hold, of/between.** The section below will probably inspire a lot of disagreement in you. But I recommend you, _fully and decisively deal with **this first section** before you deal with the section below._ Let us make an account of the exact nature and definition of _P-determines_ before we continue. ### Practical Knowledge To me, this practical knowledge stuff seems related to the Fichtean _Tathandlung_, or Act-Facts. I am quite partial to this concept, I think it absolutely essential to philosophy. I agree on distinguishing between this kind of self-realizing knowledge, and mere speculative knowledge. I actually study this in my formal system building. When I am in the room, and I deliberate, I have not decided anything yet. There is no finality to my thinking. Each thought is an action with no other immediate consequence than the thought that follows it. As I lean more towards TBing, the epistemic determination of Box 2’s contents goes futher and further towards “likely empty”. As my mind swings, and I lean more towards OBing, the epistemic determination of Box 2’s contents goes further and further towards “likely filled with $1M”. **This swinging epistemic determination happens all the while the money, or the air, sits in Box 2, completely unaffected.** It is already ontically determined, after all. It cares not for my epistemic determination regarding it. I hate to quote Ben Shapiro, but I reject his monopoly on the following truth: “Facts don’t care about your feelings.” Ontic determination does not care about epistemic determination. **The past does not care about what we learn about it.** The above preliminary swinging epistemic determination is never that strong, really. Merely thinking about TBing or OBing is not that strong evidence of what is in the box. If the predictor is 99% accurate, then my Phase 2 pre-decision deliberation will only swing the probabilities up and down within some range that is **strictly** below that 99% probability. **How do I achieve the 99% probability regarding the contents of Box 2?** Through an Act-Fact, of course. I TB. Or I OB. It is only when the action is done that I have achieved the highest achievable certainty regarding the box’ contents possible, save for actually opening it. Once I have made my decision in an unretracteable way, I know with 99% certainly what is in the box. When I open it, that 99% certainty becomes 100% certainty. In 1% of cases, the 99% certainty of $0 / $1M being in Box 2 snaps to 100% that $1M / $0 is the case. There can be a flip, and I just though I’d mention that. So, when I have just TBed/OBed, my action is both the ontic and epistemic determination of something, but they are not **of** the same thing. My action to XB is to ontically determine that “I am a Phase 2 XB.” For me to be a Phase 2 XB is heavily correlated (but not causally so) with me being a Phase 1 XB. More precisely, it is correlated with the possibility that, “I was predisposed to XBing in Phase 1”. Not _seemingly predisposed_, because we can take the strong claim and say that the predictor actually saw my rational profile and absolutely certainly established what my predisposition was, not the mere appearance of what it was. This seems to be the FDT / LDT approach when talking about “tracking the right thing”. If the predictor saw I was predisposed to XBing in Phase 1, and I YB in Phase 2 instead, we could say the predictor was correct in their assessment of my predisposition, but it just so happened that the time between the predictor’s assessment, and my action, simply changed my predisposition or somehow made me go contrary to it. This only happens 1% of the time in this scenario, but that’s not the point. I am just here modelling this situation like you seem to be: the predictor is not tracking my appearance in Phase 1, it is tracking my actual nature, my rational profile, my _true disposition to XB._ So, we could say the predictor is not even primarily predictor, but rather an assessor. The predictor is always right in their assessment, **but their assessment can be made outdated by the march of time.** It is unlikely to be so, but it could. Now, I cannot ontically determine my predisposition in the past. I cannot ontically determine anything in the past. I can merely epistemically determine it. **I cannot practically determine it either.** I can practically determine my actual behavior/categorization _right now_, through the Act-Fact that is XBing. By XBing in Phase 2, I become an XB in Phase 2, regardless of whether I was predisposed to XBing in Phase 1. This Act-Fact changes the present, not the past. My predisposition in Phase 1, which is what ontically determined Box 2, is _in the past_. It cannot be _ontically determined_, and it cannot be _practically determined_. **It can only be epistemically determined, to a certainty of 99% for example, by my XBing in Phase 2.** And _mere_ epistemic determination is not good enough. I too value the importance of self-realizing knowledge, of phenomena that are simultaneously facts and acts. **But I am not delusional regarding the reach of their influence. They are stuck in the present/future, as far as cause, ontic determination, or practical determination, is concerned.** And how does your philosophy here account for the 1% of people who either do one of two things: 1. They OB and get $0 2. They TB and get $1,001,000 My CDT thinking fully accounts for how they’re possible, exactly how they came to be, and why they collectively only make up 1% of all participants in V1 of the Newcomb Game (specifically when we say the predictor is only 99% accurate, we could change it and then just change the 1% accordingly). My thinking easily accounts for them by sticking to only _ontic_ and _epistemic_ determination, by understanding their difference and connection. I am thus able to set up the right links of _causal correlations_ and _non-causal correlations._ **There seems to be a stubborn misconcepting among OBs. You all say that two thing sharing a common cause means they are causatively correlated.** That is not what _causative correlation_ means. The term _causative correlation_ is just a weaker, or perhaps more precisem version of _cause_. When we say **X is causatively correlated with Y** , we are really saying that **X causes Y in the future, but it may have some failure rate**. It is about letting there be some room for violating the causative connection, but it is still just one thing causing another. When we **merely** learn a thing about the future or the past, we do not cause _that thing_ to likely happen, or to likely have happened: **we merely cause our knowledge thereof.** When we talk about _non-causative correlation_, it is to point out that the correlates do not actually impact each other. They do not exchange any energy or particles, they have no ontic determination on one another. **And, yet they are correlated.** Common cause correlation means that there is a third thing that causes them both to be likely. X is non-causatively correlated with Y due to a common cause \implies There is a Z such that: Z is causatively correlated with X **AND** Z is causatively correlated with Y Applying this to V1 of the Newcomb Game, I have made a diagram for you to see this more clearly. **You are always saying there is a common cause for the predictor’s prediction, and the player’s decision. I agree, but I also know this does change the correct move.** ![image](https://canada1.discourse-cdn.com/flex007/uploads/thephilosophyforum/original/1X/b5ee50e81fee4b934ae6abe46b33df85397f6d58.png) Here, we are modelling the case in which the Player’s predisposition to XBing is causes a 99% likelihood that they will XB in Phase 2. We then say this is the source of the predictor’s 99% accuracy, meaning the predictor actually _perfectly_ measures the player’s predisposition, it is just that this predisposition does not absolutely guarantee this choice in the future. There must be imperfection somewhere, or else this reduces to the perfect scenario, for which everyone here agrees OBing is correct and rational. Now, in this diagram, all _ONTICALLY DETERMINES_ relations that do not have a probability specified are 100% likely. We are of course rejecting real-life possibilities like the predictor forgetting to put $1M in the box and such, so we see that those perfect ontic determinations are indeed 100% for this idealized thought experiment. **Also, the direction of time goes left-to-right in this diagram.** Notice that ontic determination is ALWAYS going left-to-right, which is upholding the unidirectionaly of causality. The **epistemic determination** is instead going _both_ directions here, because it is symmetric across time in this scenario! Every epistemic determination here is mutual; symmetric. ## The Shape of Your Disagreement Notice that my above diagram is a collection of directed edges and vertices. My diagram is a **weighted, strongly connected digraph.** Almost\* all of the vertices who are _not directly connected_ by ontic edges are nonetheless indirectly connected through a chain of ontic edges that are all weighted at 100%, meaning we could _add_ a new ontic edge going directly between them, also weighted at 100%, with no change in the meaning. Also, using that ontically comprehensive graph (you could call it the ontic transitive closure of the graph), we could draw reciprocal, fully weighted epistemic edges between all those vertices that became connected by ontic transitive closure. This would then create the comprehensive transitive closure of the graph, with no change in the meaning, as all of these extra edges were logically inferred. **In this sense, I have a near-complete, weighted digraph.** All the vertices in this transitive closure of the graph would be epistemically connected. But exactly one pair of vertices would be ontically disconnected: **The node of whether the player gets the $1M is not connected to the node of which choice the player makes in Phase 2.** This is my account for their relationship. And these are precisely the two vertices CDT derives to be ontically unconnected! As such, this diagram **COMPREHENSIVELY** represents my entire account of Version 1 of the Newcomb Game. Therefore, if you disagree with my view, you can reduce it to something regarding my above graph, because the above graph captures the entirety of my view. As such, there are three kinds of disagreements that you could possibly have with my view: 1. One or more of the vertices are incorrect. 2. One or more of the edges are incorrect. 3. One or more vertices/edges are missing from the correct graph-theoretic representation of Version 1 of the Newcomb Game. Your disagreement with me **has to fall into one or more of those three categories.** This leads me to asking a question I think you should probably have the answer to. What two nodes are connected by your _P-determines_ relation? None of them? And what direction does this connection have? _ **Left-to-right?** _ … Or, **right-to-left?** @Sime , @FlannelJesus , @Michael , @noAxioms I don’t know if you agree with Pierre, but all of you are thinking somewhat similarly. You have some kind of special determination relation as well, _or you don’t_. In the former case, you should be able to add to my diagram. In the latter case, you should be able to change something about my diagram, without adding anything, I suspect. Why don’t you OBs draw diagrams like I do? Why do you not map out the causations and the correlations like I do? Why do you not ascribe epistemic determination to some pairs of things, and ontic determination to (other) pairs of things? **The reason is that IF you tried, you would talk yourself out of a hypothetical $1M by changing your predisposition… and you would also prove to yourself you lost a discussion, which never feels good.** But, I would argue that doing this is still very valuable. Having a truthful decision-theory will help you more generally than **maintaining the most profitable predisposition for the Newcomb Game.** I mean, that predisposition that helps you so much in the Newcomb Game will _harm you_ in the Anti-Newcomb Game, which I explained in [this post](https://www.thephilosophyforum.com/t/newcombs-paradox/298/310). **Any predisposition can harm you if the game is definitionally constructed to do so.** But a decision-theory is not judged by whether one can construct a game that, by its very definition, punishes _merely_ the _past_ _predisposition_ towards believing in that decision-theory. If this was the basis for judgement, all decision-theories would be equally bad, because any decision-theory can be “shown to be bad” through this method. **It is the application of the decision-theory that matters to the judgement of its goodness/rationality.** In both the Newcomb Game and the Anti-Newcomb Game, **applying** CDT **wins** you $1000 more, and **not applying** CDT **wins** you $1000 less. In the Newcomb Game, being **predisposed** to CDT loses you $1M. _Equivalently_, in the Anti-Newcomb Game, being **predisposed** to a non-CDT theory loses you $1M. You are missing the forest for the trees. You are letting the tail wag the dog. You are comparing apples and oranges. **The $1M that OBs won was not attainable to me, as someone predisposed to TBism.** Once I reached Phase 2, the $1M was already lost. But that $1000 was attainable, and I attained it. **And on the off-chance that I _was_ predisposed to OBism after all, then my Phase 2 TBing won my $1,001,000!** **The $1000 that OBs left was a completely free gift for them, as someone predisposed to OBism**. Once they were in Phase 2, they had already won the $1M. The $1000 was attainable at no extra cost, other than mental exertion and stress I guess. The $1000 was attainable to OBs in Phase 2, but they did not attain it (usually). **And on the off-chance that OB was predisposed to TBism after all, then their Phase 2 OBing won them no more than $0.** When you are in Phase 2, TBing can **only help you** , and OBing can **only harm you.** TBs in Phase 2 focus on the one thing they _can_ control, the $1000. And the Newcomb Game is **not** constructed to punish this in Phase 2, **but to have already punished for the predisposition of it in Phase 1** , a phase over which the players had no control. Looking at the Anti-Newcomb Game (ANG), **we see that the uncontrollable variable gets flipped.** TBs in Phase 2 of the ANG focus on the one thing they _can_ control, the $1000. And the ANG is **not** constructed to punish this in Phase 2, **nor to have punished the predisposition of it in Phase 1.** Instead, it was rewarded in Phase 1. **The past predisposition to TB** can be punished or rewarded, but this predisposition is nonetheless always uncontrollable in Version 1, by virtue of being in the past, and those games allowing for no pre-planning. **THE PAST IS THE PAST.** ## The Weak Anti-Newcomb Game Some of you may say that the (strong) Anti-Newcomb Game is too unfair. I’d say the strong version is fair in that it **lies to all players** , but it is unfair in that it rewards TBs in Phase 1. But we have the exact same unfairness in the Newcomb Game. But, you know what? I don’t even need that Phase 1 unfairness. **The Weak Anti-Newcomb Game:** 1. Participants do not know about this game, even in theory, before entering the room. 2. Before the participants have entered the room, the predictor has predicted whether they will OB or TB. 3. Box 2 **is always empty.** 4. The predictor **lies,** and presents the players with the normal Newcomb Dilemma, with the visible $1000 in Box 1, and the opaque Box 2 that is said to contain $1M if the predictor predicted the player would OB in the past. Here, all OBs get $0, and all TBs get $1000. None of the players are given an unfair advantage in Phase 1. In Phase 2, they are presented with the same lie. TBs deal with this lie by recognizing the information it claims is irrelevant to their current decision-making. OBs deal with this lie by fooling themselves into thinking it is relevant to their current decision-making, thus leaving a completely free $1000 on the table. **Here, the TBs win solely because applying CDT wins over not applying CDT.** If you say that OBing is nonetheless rational in this game despite losing, then I ask, _Why ain’cha rich?_ --- _[View the full topic](https://www.thephilosophyforum.com/t/newcombs-paradox/298)._