On Pragmatism (Column 588)

Following the debate I held a few weeks ago with Aviv Franco about the rationality of belief in God, I published a column (586) that dealt with the dispute between rationalism and empiricism, since I felt that this dispute underlay our discussion (even if not mentioned by name), and in particular that it also underlies quite a few debates between believers and atheists in recent generations. Today I received a YouTube video in which Aviv reviews the debate (and responds to the column I wrote afterward), clarifying his position and his critique of me. In this column I wanted to respond to that video. You can regard this as a continuation of the debate between us. My response was delayed because the day I received the video I flew abroad. I’ve now returned, and here are my remarks.

On the dispute between empiricism and rationalism

Aviv opens the video by citing my point that we have two toolboxes for handling this kind of claim: the scientific-empirical and the philosophical-a priori. He understood me to be claiming that they’re equal in strength, but that’s not accurate. In the end I explained that these are not really two separate toolboxes, since the observational toolbox itself rests on philosophical considerations. In my aforementioned columns I sharpened the similarities and differences between philosophy and science.

He then moves on to explain the dispute between rationalism and empiricism, and to criticize rationalism. He presents rationalism as the view that knowledge comes from thinking/logic. Again, not quite accurate. The claim is that knowledge can also (!) come from thinking. A rationalist can certainly trust—and usually does trust—the tools of observation (I certainly do). Empiricism, by contrast, holds that knowledge about the world comes only (!) from observation.

He says that my argument against empiricism is expressed by what I quoted in the column from Mark Twain—that the world owes us nothing since it was here before us. That quip expresses the fact that the trust we place in our senses and observational instruments is not grounded. Already here I’ll say that this is not accurate, precisely for the reason I noted above. I have full confidence in observation and in science as tools for knowing the world; but that very confidence is a rationalist argument. My claim wasn’t that this trust is groundless, but that it is not empiricist. From that I also explained that empiricism does not offer an alternative to rationalism, since it relies on it.

Aviv also tied this to the certainty of logic, which again is imprecise. He repeatedly identifies rationalism with logic, but that’s a mistake. Rationalism speaks about factual claims about the world (and logic does not), and accepts the possibility that such claims can be a priori (i.e., not based on observation). These are claims like the principle of causality and the like. Logic is a different category, since it doesn’t deal with the world but with necessary relations of thought between propositions. From this you can understand that I’m not claiming that a priori claims are certain the way logic is. On the contrary, I’ve said and written that, in my view, nothing is certain (apart from logic, and from this very principle: that nothing is certain). I do claim that a priori claims are not disqualified a priori. They can be admissible and reasonable, even if not certain. Logic, by contrast, is certain precisely because it lacks factual content. This is referred to in contemporary philosophy as “the emptiness of the analytic.” Logic also doesn’t deal with the world. Aviv disagrees with this, as I explained and as will be seen shortly, but here he misrepresented my position, and thus erred.

In his summary at the end of the debate’s opening survey, he said that I maintain one can present a ‘pure’ philosophical argument for the existence of God. I don’t know what a ‘pure’ philosophical argument is. If the intent is an argument detached from facts and observations, then that’s not necessarily correct. In the argument I presented I certainly rely on facts. But I process them by means of a priori tools, and therefore one cannot say that the argument is wholly observational. Yet, as I noted, that is exactly what is also done in science. The difference between this argument and science lies only in whether the conclusion is empirically falsifiable or not.

On pragmatism

At the next stage Aviv says he doesn’t want to enter this dispute because it’s a long-standing, unsettled dispute in philosophy. But again I don’t agree. Today it’s clear to anyone even slightly familiar with philosophy that there’s no place for naïve classical empiricism (as I defined in the column). At least after David Hume, everyone understands that science contains a priori components. Therefore this philosophical dispute has in fact been settled. The resolution is that there aren’t two toolboxes or two sharply distinct positions. All parties agree that one must take observation into account, but equally, for all parties, the processing of observational data is done using a priori tools. The physico-theological argument I presented was of this very character: it began from facts and processed them via a priori tools (the principle of causality). I explained that in this sense it is a scientific method, except that the product (the conclusion that God exists) is not a scientific claim because it does not stand up to falsification.

Immediately thereafter Aviv says that he also avoids this dispute because in his view it’s unimportant, since my identifying his position with empiricism rests on a misunderstanding. Aviv claims he’s not an empiricist but holds a third position: pragmatism (he returns to this in the video’s closing minutes). He explains that the dispute between rationalism and empiricism concerns how one accumulates knowledge, while the pragmatist asks what this gives me. But if so, this isn’t a third position; it’s a position that simply isn’t interested in the question of knowledge. True, philosophical pragmatism claims that pragmatic tools can also lead us to make decisions about reality (or in philosophical questions), and in that sense it would seem there is a third position. But that’s just a mistake. When you make decisions about reality, you are assuming certain claims about it. He himself says more than once that such decisions are made based on information about reality. It’s not that pragmatism offers a different way to make decisions. If so, you must now answer the question of how you arrived at the claims on which you rely. And here there are only two possibilities: the rationalist toolbox or the empiricist toolbox. The conclusion is that pragmatism tells you at most what to do with your knowledge about reality, but it is not an alternative tool for knowing reality. To tell the truth, this mistake appears even among philosophers (or those considered philosophers), and yet it’s sheer nonsense. I’ve written my critique of pragmatism as a philosophical position in several places (for example in columns 480, 496, and 501), and I won’t go into it here.

Here Aviv explains what he said in the debate. He asks: why should I care that something is true? Why should it matter to me if it’s true? It’s only a means to know what to do. But I already answered him there: if his claim is that he doesn’t care whether God exists, that’s unrelated to the claim that God does or doesn’t exist. If you got to a debate about God, you presumably do care about that question. In any case, that was defined as the debate’s topic. If it doesn’t interest you—then of course we can part as friends. But you can’t enter a discussion of whether God exists and insist on discussing whether it’s interesting and why it matters. Pragmatism is not related to the question of whether God exists, but perhaps to the question of whether it’s interesting and relevant. That’s a different question. As I explained earlier, if you want to make any decision (a pragmatic aim), you make it on the basis of factual claims about the world. And again the question returns: how do you know those claims? Here you can be a rationalist or an empiricist (and in fact a combination of both, as I explained above). You can’t evade this by appealing to pragmatism as if it were a third epistemological position. Putting pragmatism on the epistemic axis is simply a categorical muddle.

I’ll present this from a different angle to clarify the matter further. Aviv repeats over and over that reality is what decides. That’s, of course, stark empiricism. It’s not practicality that decides but observation of reality. If his pragmatism is a stance that fixes its positions according to what reality shows (what “works” in reality), then he’s simply an empiricist. Scientific observation that tests a theory likewise asks whether it works or not. If it doesn’t work, the experiment failed and falsified the theory. Hanging truth on what works is not pragmatism but empiricism. In my view Aviv is mis-diagnosing himself, or mis-defining pragmatism (he’s simply calling empiricism “pragmatism”).

The conclusion is that I did correctly diagnose the dispute between us: I am a rationalist and he is an empiricist. Pragmatism operates on a different plane and doesn’t touch the discussion we held.

Aviv’s critique of rationalism

He then does briefly enter a critique of rationalism (because he himself senses that he is indeed an empiricist, exactly as I said. Pragmatism is not an epistemological position). He claims the chief critique is that ultimately reality decides. If he means that observational findings carry weight, I fully agree. Even a rationalist position like mine, which is ready to accept principles a priori, will retreat from them if observation forces it to do so. But if he means that everything we learn is from reality, I don’t agree. Yet you will find in his words no argument at all for that position, beyond this assertion itself. I explained in the debate and in the column that there are a priori principles about which reality does not decide (like the principle of causality). This is the lens through which we view reality, and we have no observational feedback about it. But for Aviv it’s self-evident that reality decides. That’s because the position he’s presenting isn’t pragmatism but empiricism. Not only that, it’s naïve/classical empiricism (in my column’s terminology), and as I explained, it’s perfectly clear today that this is false.

Along the way he comments that a rationalist will hold to his position even if reality shows him otherwise. I, at least, don’t know such a rationalist. That’s not a rationalist stance but a delusional one. I explained above that rationalism is the view that one can arrive at claims about reality by thinking (and the empiricist disputes this). But when there’s a contradictory fact or observation, a rationalist too will, of course, abandon his a priori assumption. The “irrational rationalist” as Aviv presents him is a deranged straw man.

He then connects this to the debate we had about whether logic is an a priori truth or a human invention or the result of observation (he alternates between these latter two claims—again a contradiction in his words). In any case, here again there’s a categorical mistake. If logic is indeed learned from observation and is true only because it “works,” that’s exactly what describes a field like physics, or the natural sciences more generally. If so, on his view it follows that logic is part of the observational natural sciences, and hence he apparently thinks mathematics and logic are subject to empirical falsification. That’s truly bizarre. I’ve never heard of anyone conducting an experiment to empirically test a logical or mathematical claim. Sometimes one performs an experiment (usually computerized) to examine a mathematical conjecture that hasn’t been proved, mainly to gain different intuitions about it. But a mathematical or logical theorem that has been proved is not subject to empirical falsification (contrary to what he says in the video—that reality is not bound by our logic. A serious error, of course). Would anyone imagine conducting an experiment to check the extraction of a square root from a quadratic equation, or the length of a leg in a right triangle computed via the Pythagorean theorem? Even regarding Euclidean geometry, which might seem to have been “falsified” by Einstein, that’s a misunderstanding. It wasn’t falsified and cannot be falsified. It simply turned out that our world is not a model for it. In schools and in mathematics departments people keep studying Euclidean geometry even after Einstein’s supposed empirical “falsification.” Are they all crazy? Do they not know this has been shown to be wrong?

One must understand that science is never certain, since a scientific theory may always be falsified in the future. Mathematics and logic, by contrast, yield certain results. If they were part of the natural sciences, I don’t see how he explains their certainty. Why are there different academic departments dealing with these fields at all? In standard academic classification, mathematics and logic are not part of the natural sciences. I’ve often explained that they are branches of philosophy (see, e.g., columns 434 and 480, and the series that begins with column 155).

The example he brings to clarify his position is Zeno’s paradox. The claim is that an arrow can never reach its target, since to reach it it must cover half the distance, but to reach the half it must cover a quarter of the distance (half of the half), and so on. But in reality we all know it does reach its target. We see that reality is what decides, not logic/mathematics. This is, of course, an excellent example of Aviv’s mistake. On his view there’s no problem here at all. Observation merely shows that our mathematical/logical assumptions are incorrect. We should now throw the theory of geometric series or of calculus into the trash. In his subtext he assumes that the ‘rationalist’ (his straw man) will hold that the arrow really doesn’t arrive, even though observation shows that it does. But that’s nonsense for two main reasons. First, it’s obvious that even a rationalist will agree that the arrow reaches its target, since, as I explained, he too is bound by observation. But beyond that, precisely because of our trust in observation we see this as a paradox and immediately look to see where Zeno erred in his logical/mathematical reasoning. The assumption is not that the logical reasoning is correct but “just doesn’t work” in reality. On the contrary: if it doesn’t work in reality, we must have erred in the logic—that is, in the application of logic. Again we see that logic is not subject to change in light of observation. And indeed the solution is very simple: Zeno erred in his mathematics. The sum of an infinite series can converge to a finite value. I’ll note that in most of Zeno’s examples it’s fairly easy to show where the mistake lies. Logic and mathematics don’t function like science, where if a theory doesn’t work (is falsified) one discards it. In short, the example Aviv brought shows exactly why he himself is mistaken.

His next example is quantum theory, which he claims contradicts human logic. Again he’s mistaken—though here some physicists and philosophers (a small minority) share his error. They think quantum theory taught us a different logic (that is, that it showed our logic to be incorrect). I’ve just written a whole article on this, and I won’t go into detail here. I’ll only say that if Aviv were right that there’s a contradiction to our logic in quantum theory, then one could infer any conclusion from it (and also its negation). Logic teaches that from a contradictory system, any conclusion whatsoever follows. That is, on his view quantum theory could not yield predictions, and thus ceases to be science. I think his mistake here is very similar to the mistake he had regarding Zeno’s paradoxes (incidentally, Zeno’s arrow paradox served me in another article to explain the pathologies of quantum theory). Observation showed us that our mode of thinking was mistaken, but not that logic is incorrect. And indeed, in light of quantum theory we changed some of our assumptions (some a priori), and this is an excellent demonstration of the importance of observation—which, as noted, is accepted also by rationalists like me.

From what we’ve seen above it follows that Aviv does not accept the Kantian distinction between analytic and synthetic propositions, since he ties all rationalist thinking to logic. We now see that he essentially denies the very existence of a priori claims. For him all claims are a posteriori (that is, derived from observation). To present such a position as rational while it contradicts what almost all philosophers, almost all mathematicians (but see my series beginning with column 157 on Ron Aharoni), and almost all physicists think is a bit odd (and I’m using a blunt understatement here). Note that I’m not talking about whether he’s right, since it’s inappropriate to use ad hominem on that (as opposed to his blunt and clearly mistaken ad hominem regarding David Hume—see below). But our discussion wasn’t whether God exists; it was whether the route to Him is rational. Here it’s certainly relevant to rely on the fact that this route matches the mode of thinking of almost all philosophers, mathematicians, and scientists (though of course not all of them believe in God—that’s another debate, regarding the truth of the conclusion, not the route itself).

Back to the religious God: between deism and theism

Aviv now claims that my argument presents a very “light” divinity, i.e., an abstract one (deism). But I believe in a religious God (theism), and I also behave according to that belief. That’s true, and it came up in the debate. But in subtext he’s essentially claiming that the God whose existence I proved is not the God I actually believe in. That claim is incorrect and, with respect, unfair. As I explained there, there is no contradiction between these. My aim indeed was to argue for deism and not for theism. That was the discussion’s topic, and this was explicitly agreed upon between us in the preliminary discussion. Moreover, I explained to him there that my path to the theistic God passes through deism. In my view the philosophical stage of proving the existence of a philosophical God is a necessary and very important stage on the road to theism. If we don’t pass through it, we can’t progress. Since I estimated that we wouldn’t have time in the proposed format to make that transition—and from experience, if one skips the philosophical stage one can’t truly discuss theism—I suggested that we focus on deism. Aviv agreed to that, and so the discussion dealt only with deism. The repeated attempt to shift to the theistic God is not fair, since we agreed not to discuss Him now. Nor is it correct, because I certainly have rational arguments to reach theism as well, which does not contradict deism. After proving the existence of a deistic God, there’s nothing to prevent arguing that He also revealed Himself and commanded, etc. That, of course, will require further arguments, but there is certainly no contradiction between an argument for deism and a theistic conclusion.

If, as a pragmatist, he isn’t interested in this discussion or doesn’t think it important, he could have objected to holding the debate or proposed something else. But it’s neither fair nor reasonable to agree to a debate on deism and then complain that we aren’t dealing with theism. It’s hard for me to ignore the sense that this relates to the weakness of his arguments on the deistic plane.

His opening

At this point Aviv reviews his own opening. He repeats his claim that to argue for God’s existence we have to think of two possible worlds: in one God exists and in the other He doesn’t, and the question is what action I should take to ascertain His existence or non-existence. He presents this as pragmatism, but it’s simply empiricism. He’s really asking what the empirical indicator of God’s existence is, or, in other words, what experiment could falsify or confirm His existence. That’s a thoroughly empiricist question. It has not a hint of connection to pragmatism. Note that the “action” he speaks of is an experiment or phenomenon that would test or attest that God exists. Therefore, translated, he’s merely saying here that the claim that God exists is not subject to falsification. As an empiricist he thinks that what is not subject to falsification is not true or at least there’s no reason to assume it’s true, but I began by saying that as a rationalist I think otherwise. A philosophical argument can also serve as such a basis. I don’t see what this repetition added.

Time and again you can see that the dispute between us is a dispute between an empiricist and a rationalist, exactly as I explained, and there’s no connection here to pragmatism. If he wanted to ground it on a pragmatic basis, he should have asked: what should I do in the world with God to live better and more correctly, as opposed to a world without God (and the answer—at least regarding a theistic God: keep the commandments). But the question he asks is different: what action will reveal His existence. That’s the posing of an empirical falsification test—i.e., an expression of empiricism.

I’ll now just touch on a few points that appeared later which nevertheless need sharpening.

The dragon

Aviv responds to the addition I made in the column regarding the dragon under the table. I said there that if I saw a table floating in the air and had no other explanation, I’d be prepared to accept the claim that there’s a transparent dragon beneath it holding it up. That is, I distinguished between asserting something about the existence of a dragon and bringing evidence for its existence. Aviv claimed that I set up a straw man, because he too agrees that if there’s evidence we’ll accept the claims about the dragon. But I wrote explicitly that we likely agreed on this, so I don’t understand his claim against me. For some reason he again lapses into the confusion between a claim about existence and evidence for it.

Immediately afterward he rejects my example of the floating table because there could be countless other explanations. Well, I know that too (and therefore I too am not inclined to accept the existence of dragons). He also adds that the fact that there is a possible explanation doesn’t make it true. Of course. Who disputes that?! He ignores the fact that precisely for these reasons I explained that I’m assuming for the sake of discussion that there is no other explanation, since the example is brought only to illustrate the difference between a claim and evidence. On the assumption that we have no other explanation, would we not accept the dragon explanation? Would we regard it as irrational? How is this comparable to someone’s claim about the existence of a dragon without any indication? Aviv keeps returning to the confusion between claim and evidence. This example serves only to clarify the point that, given evidence, Aviv too would accept the existence of a dragon (just as he accepts the existence of an electron, an electromagnetic field, the Higgs boson, etc., by virtue of indirect evidence even if we do not see them). That’s a simple matter that the example clarifies well. Anything beyond that was never claimed by me.

But there is a substantive issue here, because all along Aviv ignores the explanation I added in the column. I said that although we agreed that given evidence we’d accept the dragon’s existence, a dispute remains between us about the possible nature of such evidence: is it only empirical observation or also a philosophical argument? Aviv takes for granted that only empirical observation is relevant evidence, since he is an empiricist (despite his denial). Again you can see that our dispute is between empiricism and rationalism, of course.

Proof by elimination

He then discusses the meaning of a proof by elimination. He says that if I’ve rejected one explanation, that doesn’t prove the truth of a different explanation, since there may be many other explanations. That’s entirely clear and needs no elaboration (as we saw in the previous paragraph regarding the dragon). But in applying this to the physico-theological argument, he adds another mistake, as I’ll now explain.

First, I’ll recall what I wrote in the column: in the debate Aviv alternated between two contradictory claims—there is no explanation, and perhaps there’s some other explanation. The option “there is no explanation” cannot serve as a rational alternative. It may be true, but as you’ll recall, my aim was to show that there is a rational route to belief in God. If so, it’s entirely rational to assume there is an explanation—and I’ll gently add that the claim “there is no explanation” is certainly not preferable or more rational.

Second, my claim is that if there is any explanation at all (an explanation, for our purposes, is something that produced the complexity—since complexity does not arise by itself at random), whatever it may be, that is God. As you’ll recall, we’re dealing with deism. I didn’t speak about commandments and behaviors that God commands and obligates, and therefore I didn’t say anything about who or what that God is. If I had proposed a particular explanation, one could have argued that perhaps there’s some other explanation. But I’m discussing the question whether there is some explanation at all, without entering what it is. Regarding that general question there are only two logical options: either there is an explanation or there isn’t. There are no further options.

If you reject the option that there is no explanation (including the option of an infinite regress, as I explained there), since it is less rational, and certainly not more rational, then the conclusion that there is an explanation is indeed rational (and in my view also more correct—but as noted, that’s not our topic). The conclusion is that there is something or someone that produced our complex world. I didn’t say a word and did not commit myself to anything regarding the nature or character of that cause. For me, whatever produced the world is the God I’m talking about. Thus this is a standard proof by elimination: if we’ve ruled out the “no explanation” option, then there is an explanation. Here there’s no place at all for the claim that “perhaps there’s another explanation.” It’s no wonder that when Aviv explains this supposed “fallacy” he chooses specifically to use the dragon example and does not turn to the physico-theological argument, since there he cannot make the claim he’s making.

Naturally, one can discuss counter-arguments such as the anthropic principle, multiverses, and so on. But we didn’t reach any of that in the debate, and in my book The First Being I address them all. As far as what arose in the debate, there was a straightforward logical proof by elimination, and the “fallacy” Aviv points to is simply irrelevant to it.

Begging the question

Aviv then turns to the fallacy of begging the question. I’ve explained more than once that there’s no fallacy here (see, for example, the thread here), and the examples he brings are all beside the point. Every valid logical argument “assumes the conclusion”; otherwise it wouldn’t be valid. The reason that if one accepts the premises one must accept the conclusion as well is that the conclusion is contained in the premises.

I must note that his formulation of Anselm’s ontological proof—“God is existent, therefore He exists”—could serve as a canonical example under “straw man” in an encyclopedia of ideas. Whoever is interested can see the correct formulation of that argument in the first conversation of my book The First Being, and there learn why that argument is far from being as silly as it is typically presented by people who don’t understand it.

The “fallacy” of the special case

The “special case” fallacy he insists on is not a fallacy. Aviv’s description of the fallacy is as follows:

The principle X is always true except in case a. Why? Just because.

But again he sets up a straw man. One can certainly speak about the problematic nature of adding ad hoc assumptions or ad hoc exceptions (that prevent falsification). But these aren’t fallacies; they’re weak claims. Yet none of this is relevant to us, since in our case we’re not talking about adding an ad hoc assumption. Again Aviv confuses a claim with evidence, exactly as we saw above.

I explained that my claim—that God departs from the principle of causality—is based on indications and not on a mere assumption or conjecture. The argument is that denying it leads us to an infinite regress (I won’t re-enter that here; as noted, this is explained in my book The First Being, conversation two). Therefore this is a proof by elimination that there must be a link in the chain that is primary, i.e., does not require a prior cause.

The remaining objections

He then adds a few more objections to my argument itself, such as why I accept that God has no cause but the laws of nature or reality do need a cause. Later in the video he says that the universe, in fact, is for the most part not complex and ordered, and therefore overall does not have low entropy.

As I explained above, I don’t see a point in addressing these here, for several reasons: (1) Our discussion is not whether my argument’s conclusion is true but whether the argument is rational. (2) All these objections are answered in detail in my book above. Briefly: the first question I’ve answered many times here as well (regarding God I have an indication that He has no cause. That’s not a claim but a conclusion from an argument). Regarding the second, I explained in the book that I’m not dealing with the second law of thermodynamics, and therefore entropy was brought only to explain the notion of complexity and as an answer to his claim that complexity has no objective definition (only a comparative one). That’s simply a mistake he keeps repeating here; the very existence of the concept of entropy in our physics shows this. I also already addressed the question of the origin of the principle of causality in the column.

David Hume and ad hominem

Earlier I noted ad hominem, and at this stage Aviv blatantly commits this fallacy. The fact that David Hume lived many years ago says nothing about his positions. He claims that had Hume known modern scientific information, he would have changed his view of the principle of causality. That’s a shocking philosophical misunderstanding, but beyond that it’s ad hominem. First, he didn’t show how the new information is relevant (and not by chance—because it isn’t relevant to the philosophical discussion in any way), and he attacks not the claim but the person who made it. In my argument I did not rely on Hume personally, but on his argument (that causality is an a priori principle).

Continuing his remarks on Hume, he discusses gravity. He explains that if we don’t see it that doesn’t mean it doesn’t exist, since reality says that it exists. In what sense? We see the phenomena it produces. Well, it’s unpleasant to repeat that this is empiricism, not pragmatism. But to the point, there’s ambiguity, misunderstanding, and perhaps even contradiction in his words. The ambiguity (and perhaps contradiction) is that he shifts between arguments for the existence of gravitational force based on the phenomena it produces, and arguments that this force is only a description of motion and not an existing entity in itself. Either way, it leads to the conclusion that Aviv is mistaken. Why? Because if the claim that there’s a gravitational force is only a rephrasing of the claim that bodies have acceleration (since we see the acceleration but not the force), then Newton’s second law (the relation of force to acceleration) is a definition, not a law. I don’t know of a physicist who thinks that. Beyond that, the fact that physicists invest enormous resources and effort—and most of them do so with full confidence—in discovering the existence of gravitons, shows that they think the force of gravity is an existing entity and not merely a way of describing bodies’ motion. The assumption is that there is a force (or a field), and since there is no action at a distance, there must be particles that mediate that force from place to place. If it were only a description of motion, there would be no place to search for gravitons. Behold: when physicists speak of the existence of gravitational force they are speaking of something ontic, and this without having seen it. The phenomena we see with our eyes (motion and acceleration) lead us—by analysis that uses a priori principles as well—to the conclusion that there is a cause that produces those phenomena. Ring a bell? That’s a straightforward physico-causal argument.

Does the principle of causality operate “outside reality”?

Aviv claims that I apply the principle of causality outside reality. That’s only partly true. First and foremost I apply it to our reality. I claim that our reality must have a cause. Even if the cause is something outside our reality, the principle of causality is applied here to reality itself.

But beyond that, I don’t understand what “outside reality” means. That’s an expression Aviv coined; you didn’t hear it from me. He speaks of the existence of something that is “nothing,” and points to the nonsense in that. But I fully agree—that’s his nonsense (again he attacks a straw man), not mine. For me, God is part of reality, since I began by saying that when I speak of belief in God I’m talking about a factual claim. He’s not part of physical-material reality, but He exists. Therefore, by definition, I’m not applying anything outside reality. I’m certainly prepared to accept the existence of reality beyond physics, and indeed I’ll apply the principle of causality to it as well unless there’s a good (!) reason not to (as with God).

Paley’s argument

It’s odd to me that when coming to refute Paley’s argument Aviv spends long minutes repeating the same mistake I already explained to him in the debate and reiterated in the previous column. There is no difference between an artificial object and a natural object. Complexity always requires an explanation (i.e., a cause). That’s a simple statistical consideration. Yet with respect to a natural object we have a ready-made answer: God (and Aviv will say: nature; and then I’ll ask him whether that is an explanation or that he has no explanation). But regarding the complexity of an artificial object, it seems to us it’s not God, and therefore specifically about it we ask: so who is it? That’s the whole difference.

His mistake here rests on his earlier erroneous assumption that complexity is a matter of comparison, and therefore complexity as such does not require an explanation. We have seen that complexity has an objective definition (via entropy), and I claim that it certainly requires an explanation. This argument is statistical (it’s unlikely that a complex thing will arise by itself without a guiding hand), and therefore it is not tied specifically to experience (contrary to Aviv’s repeated assertion).

Regarding his claim that there are countless explanations for why Paley’s argument fails, I’ll merely note that I don’t know even a single such explanation, and as we’ve just seen, the explanation he offered here certainly isn’t one. In my view it’s an excellent argument, eminently rational, and in my book God Plays Dice I explained that it’s merely a popular garb for the physico-theological argument, and I also showed that those who attack it simply don’t understand it.

The timeline and causality: infinite regress

Before the end, Aviv returns again to the question of time and causality, proposing the possibility that time is infinite (and entirely compressed at the Big Bang singularity). I assume that in physics I understand a bit more than he does, but I won’t exploit that here because this argument is irrelevant. I don’t want to enter the apparent contradiction in this description: is the time axis of zero length or of infinite length? I know of the contraction of objects in space, but what is the meaning of contraction of space itself? Within what (or relative to what) is it contracting? And so too regarding time. These have possible explanations (intrinsic curvature in mathematics and physics), but that requires geometry and advanced measure theory, and I won’t go into it here.

What matters more for our purposes is what Aviv gains by proposing to compress the time axis to a point and by speaking of its infinite length that is compressed inside there. How is this supposed to refute my argument? He didn’t explain this, but I surmise he means the argument he briefly raised in the debate—that an infinite regress is not necessarily a fallacy because perhaps time is of infinite length. If the time axis is infinite, then in his view there’s no impediment to accepting an infinite explanatory chain.

But I answered that in the debate and in the column. I explained that, contrary to his assumption, time is not a necessary component in the causal relation. The problem with an explanatory regress of the infinite type is not tied to the length of the time axis. Moreover, I wrote that an infinite chain of causes can fit in finite time even without topological compressions, simply via a model in which each link in the causal chain lasts half as long as the one that follows it. That’s all. There’s no need here to invoke the Big Bang and modern physics. So if the problem were the time axis, it wouldn’t exist at all. If that were the problem, I would accept explanations involving an infinite regress. But none of this is relevant, because even if the time axis were infinite, that doesn’t help Aviv. The flaw in an infinite regress is not about how long the causal chain lasts, but that an explanatory regress presupposes an actual infinity, not a potential one. I explained this in my book The First Being, conversation two.

To be brief, I’ll explain it this way. To present an explanation for some phenomenon, you must begin at the beginning and progress up to the event you’re explaining. You cannot progress backward—i.e., present an initial explanation for the event, then another explanation for that explanation, and another for that explanation, and so on, proceeding backward to infinity. The reason is that if you present an explanation in that way, you have not presented an explanation. That’s exactly the “explanation” of ‘turtles all the way down.’ Think of walking along the X-axis leftward from the origin. You will not reach the end after infinite time. You will never get there, simply because there is nowhere to get to.

It’s easier to see it as follows. You cannot define mathematically the reverse process whereby one begins walking rightward from minus infinity and then, after infinite time, reaches the origin. That process is not well-defined mathematically, because its definition contains a point that is undefined (and does not exist). Think, for example, how you would compute the time it takes for our walker to reach the point X = –1000 km, or X = –253,451,997,2340 km? So it is for every point on the path. Our walker will never reach any point on that path; that is, there is no path here (a path is defined as a function X(t) that gives me position as a function of every point in time).[1] By contrast, the process of walking leftward is well-defined; it just has no end. The process of walking rightward from minus infinity is not defined at all because it cannot begin. Therefore an explanation in the form of an infinite chain is no explanation. But this is not the place to expand on this further.

[1] Incidentally, this is the mistake of the author of Chovot Ha-Levavot (“Duties of the Heart,” in the Gate of Unity) and other ancient philosophers, who brought an argument against the view of the world’s eternity from the claim that if the world were eternal, we would never have reached our present day.