Monday, November 29, 2010

Theistic Presentism cont.

This is the eighth of 17 posts, which are collectively Eternity, etc.
......The Presentist present is not so much a time as reality. A line with dynamic (and continuous) branches may give Presentists a reasonably accurate picture of how continuants change, but that dimension is only figurative. Nothing real is literally inside it. And while it’s only common sense that we exist within time, we are dependent creatures, currently subject to physical laws in the shadow of death. By laying down our temporal constraints, the Presentist God in a sense created time as we know it, which He transcends. Furthermore He was, is or will be at all such times, and is everywhere immanent. The atemporal God also created time, of course (as a real dimension), and is in a sense spatiotemporally omnipresent [i]. So while there is a sense in which the everlasting God is inside—the timeless God outside—time, it is often more accurate to think of the former as able—the latter not liable—to change.
......As Mawson discussed atemporalist spatiotemporal omnipresence, he mentioned—the second of our three reasons—that “of course scientists are happy to talk of space and time as merely two aspects of a unity, space-time[ii]. But to begin with, such talk is generally an unreliable guide to ontology [iii]. And in particular, the evidence for relativistic physics is quite compatible with there being an absolute present [iv]. Furthermore, many physicists are unhappy with the picture of time as quasi-spatial, because they take quantum mechanics to be describing the collapses of wave-functions that represent current physical tendencies towards the possible outcomes of such collapses [v]. Such physical possibilities interact as such, even though most won’t have been how things actually were. And that implies the current reality of (what will have been) the non-actual—in the sense of the Actual World of popular (4-Dimensionalist) Possible Worlds semantics—or in other words, that the future is partially unreal.
......[i] Mawson, Belief in God, pp. 48–51.
......[ii] Ibid, p. 51.
......[iii] Similarly, neuroscientists are generally happy to talk of the mind as though it was nothing but an aspect of the brain, and such talk hardly means that we are unlikely to be incarnate spirits if there is a God; ibid, pp. 93–9; Swinburne, Is There a God? pp. 70–94.
......[iv] Richard Swinburne, Space and Time, 2nd edition (Macmillan, 1981), pp. 177–205; William Lane Craig, Time and the Metaphysics of Relativity (Kluwer Academic, 2001); John Polkinghorne, “Time in Physics and Theology,” in Poe & Mattson, What God Knows, pp. 61–74; Dennis Dieks (ed.), The Ontology of Spacetime, Vol. I (Elsevier, 2006); Bourne, A Future for Presentism, pp. 141–203.
......[v] For more details, see Roger Penrose, The Road to Reality: A complete guide to the laws of the universe (Jonathan Cape, 2004), pp. 493–608; Karl R. Popper, The Open Universe: An argument for Indeterminism (Hutchinson, 1982), pp. 87–109.

Saturday, November 27, 2010

Theistic Presentism

This is the seventh of 17 posts, which are collectively Eternity, etc.
......The concept of time arises as we relate to the regular changes of such continuants as the earth, or a clock. A continuant is anything that is wholly present when it exists—e.g. you may lift up the whole clock—and which continues to be the same thing as its attributes change—you can put the same clock down later. Many of our quotidian beliefs concern such continuants as the ordinary objects around us. So our quotidian beliefs presuppose (and hence imply) something like Presentism [i]. And if you think about it, you can be justifiably certain that you are a continuant. And Presentist Theists take God to be the original continuant. So whether the Presentist Open God changes or not, He is bound to remain the same person, with the same essential attributes. He is not changeable, like a pagan god, but perfectly constant in His absolute power, and boundless love.
......Consequently He might know infallibly that He will—if He has decided that He will—sustain the earth, at least until tomorrow. It is His choice—He has the power not to—but if God determines to stay on some freely chosen course, then there being no real chance of Him deviating from it would surely confirm, rather than compromise, His perfect freedom, His omnipotence. (Cf. the classical distinction between absolute and ordained power.) Surely having the power to do X might cohere with there being no chance of X actually happening. We are, after all, regarding libertarian atemporalism as a prima facie logical possibility. So in short, it may well be false that, under Open Theism, and “given that the world’s having a future at all is dependent on God’s freely choosing to sustain it from moment to moment […] He does not have infallible knowledge of the future of the world in any respect at all[ii].
......The underlying problem appears to be how easily Presentism is misunderstood. As we try to understand time—to see more clearly what it is like—we very naturally focus upon its quasi-spatial representation, the temporal dimension. Consequently some philosophers think that Presentism faces the dilemma—the first of our three reasons—that the present is either temporally extended, as though earlier and later could possibly be simultaneous, or else it is only an instant, at which no one could be having such sensations as we clearly are having [iii]. In fact, the Presentist present is not extended (except spatially), but enduring. Nor is it thin—as though the future rained down upon the surface of the past but only that surface was real—because it includes the whole world (as a collective continuant) and, for Presentist Theists, the whole being of God.
......[i] Cf. Mawson, “Divine eternity,” p. 41 n. 4.
......[ii] Ibid, p. 38. Here “world” means the whole of creation; Mawson, Belief in God, p. 10.
......[iii] For more details, see H. Scott Hestevold, “Presentism: Through Thick and Thin,” Pacific Philosophical Quarterly 89 (2008): 325–47.

Thursday, November 25, 2010

Future Contingents cont.

This is the sixth of 17 posts, which are collectively Eternity, etc.
......Ordinary language is vague (see previous post), and the main thing here is that indefinite is not an unreasonable original truth-value under Presentism (given libertarianism), as follows.
......Under Presentism there would have been, before reading on, or not, those two (metaphysical) possibilities for how things could have turned out, not just the one (actual) future. So your belief about the future would not originally have concerned anything definite (insofar as your belief concerned the future directly, rather than via your intentions). The future is not completely definite under Presentism [i]; or in other words, the Presentist future is not completely real, in the sense that not all the statements about it that will ever have been correct are now true.
......As aforementioned, the future might be partially real—be what Mawson calls “real”—under Presentist Open Theism, because then it might be false (see section IV) that “there aren’t any true statements concerning future states of affairs at all[ii]. However, the reason given by Mawson for the future being real was that some future contingency will either happen or not, and that if “we assume for the sake of argument that [it will] then that’s a fact about the future that someone could in principle have beliefs [about][iii]. And while it will either happen or not, as a matter of logic [iv], to presume that one of those two is already a fact is to reject (or ignore) the following picture of Presentist time, as dynamically branching.
......Presentists tend to picture the past as the trunk of a tree whose branches represent the future, one branch for each possible future [v]. If some future contingency does happen—and similarly if it does not—one could in principle look back down the single timeline of the past that includes it happening (or not), and see that fact with hindsight. Further back, and the contingency would definitely be going to happen (or not), but only with hindsight. At the time, it was one of two (metaphysical) possibilities.
......Since Mawson was right that Perfect Being Theists can, quite properly, be agnostic about theories of time [vi], and since the (logical) possibility of Presentism undermines—or at least reduces the significance of—his primary argument, the next section will further describe that possibility, and thereby answer three popular reasons for rejecting it.
......[i] The future is completely definite under 4-Dimensionalism (aka Eternalism); Michael Rea, “Four- Dimensionalism,” in Loux & Zimmerman, The Oxford Handbook of Metaphysics, pp. 246–80.
......[ii] Mawson, “Divine eternity,” p. 37.
......[iii] Ibid.
......[iv] The ordinary meaning of “not” is all the logic we need here. The complicating factor is that, as aforementioned, “X will happen” can mean both that X will definitely happen and that X will, as it turns out, happen. Consequently “Either X will happen or else X won’t happen” is also ambiguous. For more discussion, see Rhoda, “Generic open theism,” p. 231.
......[v] For such pictures, see Denyer, Time, Action and Necessity, p. 12; Bourne, A Future for Presentism, p. 62.
......[vi] Mawson, “Divine eternity,” pp. 40–41.

Tuesday, November 23, 2010

Future Contingents

This is the fifth of 17 posts, which are collectively Eternity, etc.
......Mawson’s primary argument against Open Theism was essentially as follows (the details differ [i]). When you finish reading this paragraph, you will either begin the next one more or less immediately, or else you will do something else for a while. And whichever it is that you actually do, if you now believe that you are going to do it, you would, it seems, be having a true belief about the future. But you might change your mind (you have libertarian freedom), so under Open Theism God should not now be certain that you are going to do it. Might He guess that apparent truth? [ii] But if the Open God knows perfectly well that He is epistemically infallible, then He is certain of whatever He believes. So this kind of argument is essentially that He is not omniscient.
......Nevertheless, it is because you have libertarian freedom that, unless your belief turned out to be false, either you just made it true by continuing to read, or else you made it true a while ago. There is therefore the conceptual possibility, at least, that your belief was originally of indefinite truth-value, neither true nor false (if very likely) [iii]; and that possibility yields one of the two or three commonest varieties of Open Theism (another being Swinburne’s) [iv]. And according to this variety, God can be (necessarily) omniscient, because not knowing something that is not true would clearly not obstruct (necessary) omniscience.
......Now, even if your belief originally had a probability between 0 (false) and 1 (true), “indefinite” might be used to denote all such probabilities (collectively or indiscriminately). So a third truth-value called “indefinite” is essentially what such an indefinite truth-value is. And those defending this variety should perhaps “motivate and defend the denial of bivalence and the attendant departure from standard logic.” [v] So note that there are many reasons for denying bivalence and moving on from our most elementary logic (e.g. see section VII) [vi].
......Swinburne retains bivalence at the cost of omniscience. Such Open Theists think that your belief was originally true or false according to how things turned out. And indeed, had you guessed correctly, your belief would—in that sense—have been correct. Still, had someone originally believed that she would read on, and later thought “I was right,” she might have meant by that only that she had read on (with no thought for how well her belief had originally described what then existed). Furthermore, since she might not have read on, there is also a sense in which her “I will read on” would originally have been false. Nevertheless, although a third variety of Open Theism does call the original truth-value “false” (and so hopes to retain bivalence as well as omniscience) [vii], her “I will read on” need not have meant that she would definitely read on (which was false), rather than that she would happen to read on (which she did), or indeed, that she would probably read on, or had intended to. Such is ordinary language.
......[i] For more details, see Mawson, “Divine eternity,” p. 37, pp. 44–5. For similar arguments, see Helm, Eternal God, p. 67; Swinburne, Is There a God? pp. 7–8.
......[ii] Mawson hoped to show the Open God making mistakes (see section V), but later accepted that He might be epistemically infallible; Mawson, “Divine eternity,” p. 45.
......[iii] For more details, see Elizabeth Barnes & Ross Cameron, “The Open Future: Bivalence, determinism and ontology,” Philosophical Studies 146 (2009): 291–309.
......[iv] For more on this variety, see David Kyle Johnson, “God, fatalism, and temporal ontology,” Religious Studies 45 (2009): 435–54. This variety was distinguished from Swinburne’s by Helm, Eternal God, pp. 109–21. For three varieties, see Rhoda, “Generic open theism,” pp. 229–32.
......[v] Ibid, p. 231.
......[vi] For further reasons, see Grzegorz Malinowski, “Many-valued Logic and its Philosophy,” in Dov M. Gabbay & John Woods (eds.), The Many Valued and Nonmonotonic Turn in Logic (North-Holland, 2007), pp. 13–94.
......[vii] For more details, see Alan R. Rhoda, Gregory A. Boyd & Thomas G. Belt, “Open Theism, Omniscience, and the Nature of the Future,” Faith and Philosophy 23 (2006): 432–59.

Sunday, November 21, 2010

Divine Attributes cont.

This is the fourth of 17 posts, which are collectively Eternity, etc.
......As aforementioned, God is the ground of metaphysical possibility, if He exists. Let us assume that He does (if only for the sake of agnostic argument). (And let us also assume libertarianism, if only because Mawson’s arguments do). Since God is, presumably, the greatest conceivable being, we can again follow Mawson and say that He is omnipotent, where “an omnipotent being is a being with the most power-granting set of abilities that it is logically possible anyone might have[i]. It seems to follow that God is infallible, since being able to make mistakes would surely detract from His overall power [ii]. The Open God might be epistemically infallible, for example, in virtue of His beliefs being held by Him only insofar as they are completely justified [iii].
......Does it also follow that God is omniscient (see previous post)? Each possible fact might be associated with a power to know it. But that might be a power to know it eventually. Would it be more power-granting for God to know now all that He will ever know, or for Him to be able to know anything desired as quickly as desired? It’s hard to say, but it seems that the most powerful God is able to increase His knowledge (see section VII), which would stop Him having what Mawson calls “complete omniscience[iv], but would not obstruct His necessary omniscience (see section VIII).
......What is relatively clear is that God is eternal, i.e. without beginning or end. That is clearly so if God transcends even the possibility of change. But even the Open God is necessarily unending, because there should never be any real (metaphysical) possibility of the ground of all good things not existing. And if the Open God had some primary state, prior to all His other states, we might regard that as time having its beginning in Him, rather than vice versa (see section IV) [v]. So, God is eternal; what is less clear is whether He is timeless or everlasting. Indeed, even that question’s terms can be questioned.
......Mawson’s terms—“atemporal” and “temporal”—were not too bad, being less biased towards atemporalism (aka Eternalism) than were the traditional terms, “eternal” and “sempiternal” (following Boethius). But whereas both “timeless” and “everlasting” connote unfading immortality, “temporal” connotes limitation. E.g. it can also mean civil or secular, as opposed to sacred or spiritual. And crucially (see section IV), the Presentist Open God does not exist inside the sort of temporal dimension that the atemporal God transcends [vi]. To avoid begging the question, and to stay apposite [vii], I suggest that we call God “timeless” if He transcends, not only spacetime, but even the possibility of change, and call Him “everlasting” if He is so involved with us that the future is open (in the sense of Open Theism).
......[i] Mawson, “Divine eternity,” p. 41.
......[ii] For more details, see Mawson, Belief in God, pp. 28–35.
......[iii] For a possible problem with that, see Omniscience and the Odyssey Theodicy.
......[iv] Mawson, “Divine eternity,” p. 37. “A completely omniscient being cannot learn anything,” ibid, p. 41 n. 5.
......[v] See also William Lane Craig, “God, Time, and Eternity,” in Harry Lee Poe & J. Stanley Mattson (eds.), What God Knows: Time, eternity, and divine knowledge (Baylor Univ. Press, 2005), pp. 75–93.
......[vi] See also Alan G. Padgett, God, Eternity and the Nature of Time (St. Martin’s Press, 1992).
......[vii] I am ignoring immutable temporal Deities. And according to my definitions, God would be neither timeless nor everlasting if He was able to change but had already created our future (see note v of Possible Worlds).

Friday, November 19, 2010

Divine Attributes

This is the third of 17 posts, which are collectively Eternity, etc.
......I shall, then (see previous post), be arguing that Open Theists can accept God’s necessary omniscience, in the sense of His being bound to know each truth whenever it exists (insofar as truths exist). Richard Swinburne—the Open Theist that Mawson focused upon—disagrees; or rather, Swinburne thinks that because of future contingents (see section III) we should “understand God being omniscient as God knowing at any time all that [it] is logically possible to know at that time[i]. But let us follow Mawson, and “say that a being is omniscient just if it is the case that for all statements, if a statement is true, then that being knows that it is true[ii].
......It would be natural for atemporalists to take truth to be timeless, however. (Indeed, even Swinburne seems to do so.) So Mawson may well have meant, by the phrase “if a statement is true” in his definition, if a statement is ever true. But there are many reasons, e.g. Cantor’s Paradox [iii], why truth is not timeless. And whatever the merits of such arguments, our question here is whether God—who may well be the ground of truth—must be timeless. We should therefore avoid begging the question, as we use Mawson’s definition, by not also assuming that statements cannot change their truth-values.
......Of course, Swinburne’s position is, to say the least, not obviously incoherent. So I would not say that the Open God’s omniscience (in our sense) is logically necessary. A logical possibility is primarily a coherent conceptual possibility, logic being the study of correct reasoning. What I will be defending is the logical possibility—indeed, the plausibility—of a variety of Open Theism under which God is bound, of metaphysical necessity, to be omniscient. Metaphysical necessity generalizes the natural (non-Humean) laws of physics so as to allow for such non-physical things as spirits and to allow for miracles and other possible creations (e.g. a new earth) [iv]. And if there is a God, then all metaphysical possibilities would be grounded in Him.
......[i] Swinburne, Is There a God? p. 8.
......[ii] Mawson, Belief in God, p. 35.
......[iii] If there was a set of all the other sets, then via Cantor’s Diagonal Argument (see section VII), there would be more subsets than there are sets; but each subset is a set, so there is no set of all the other sets. That would be paradoxical if “set” meant things referred to collectively. And since for each set there are such truths as what its members are, so there is no set of all truths; Patrick Grim, “There Is No Set of All Truths,” Analysis 44 (1984): 206–8. The result that truth is not timeless follows if “set” is given its informal meaning, of an immutably complete collection. For other arguments to that effect, see Nicholas Denyer, Time, Action and Necessity: A proof of free will (Duckworth, 1981), pp. 79–82; Richard Sorabji, Time, Creation and the Continuum: Theories in antiquity and the early Middle Ages (Duckworth, 1983), pp. 132–5.
......[iv] For more details, see Mawson, Belief in God, pp. 65–7.

Wednesday, November 17, 2010


This is the second of 17 posts, which are collectively Eternity, etc.
......In this debate, “God” refers to the perfect person—or Trinity (but nothing impersonal)—who created everything else ex nihilo [i]. If such a God exists, He (they, she) created us, so such Theists naturally think of Him as the greatest conceivable being; and Open Theists are no exception [ii]. Open Theists are so-called because they believe that God keeps some of His options open, as He relates to us [iii]. Such divine openness follows from the sort of freedom (responsibility, creativity) God gave to those made in His image. Open Theists take a libertarian view of free will. And atemporalists—who think that God transcends even the possibility of change—can also take that view [iv], according to Mawson:
On the libertarian view of free will (as it is standardly construed), all that has to be true for you to be free in the future in your choice to do X is that you have the power at that time to do something other than X and on atemporalism you can have this power—have the power to make God either have the atemporal belief that you do X or the atemporal belief that you don’t do X—without having the power to make any belief He actually has false. [v]
The future being what Mawson calls “real” (“that some statements concerning what is now the future are true”) is relatively uncontroversial. Even Presentist Open Theists might think it true that, for example, the earth will still be here tomorrow. “Presentism is the view that only what exists now has any reality[vi], but what exists now—e.g. an egg falling—could determine how something will be—e.g. the egg breaking—via the laws of nature, and God’s constancy (see section IV), and so make it true now that such will be the case.
......I argue in section IV that Presentism is not implausible under Perfect Being Theism. Mawson’s primary argument—that because of future contingents (see section III), the Open God lacks some infallible knowledge of the future—therefore lacks the significance attached to it by Mawson. Under Presentism, the Open God can be infallibly omniscient (see section III). Presentism can also explain why the Open God is essentially constant, and hence why Mawson should not have thought of the Open God as having no infallible knowledge of the future. And Mawson’s main argument—that by being incompletely omniscient, the Open God is liable to make mistakes—was based on a misunderstanding of Open divine action, according to section V.
......Section VI initiates a more direct comparison of Presentist Open Theism with libertarian atemporalism. Section VII is based on Cantor’s Paradox and is an informal mathematical argument that the numbers of things within possible creations are indefinitely extensible. God’s omnipotence therefore indicates that His knowledge of whole numbers is forever increasing. And I also suggest in section VIII that under Presentism He could, even so, be necessarily omniscient.
......[i] Mawson, Belief in God, pp. 9–27.
......[ii] Richard Swinburne, Is There a God? (Oxford University Press, 1996), pp. 3–19; Alan R. Rhoda, “The Philosophical Case for Open Theism,” Philosophia 35 (2007): 301–11; Alan R. Rhoda, “Generic open theism and some varieties thereof,” Religious Studies 44 (2008): 225–34.
......[iii] For more details, see Charles H. Pinnock, Most Moved Mover: A theology of God’s openness (Baker Academic, 2001).
......[iv] Not all atemporalists do, e.g. see Paul Helm, Eternal God: A study of God without time (Clarendon Press, 1988).
......[v] Mawson, “Divine eternity,” p. 40. For more details, see Timothy O’Connor, “Dualist and Agent-Causal Theories,” in Robert Kane (ed.), The Oxford Handbook of Free Will (Oxford Univ. Press, 2002), pp. 337–55.
......[vi] Rhoda, “Generic open theism,” p. 234 n. 22. For more details, see Thomas M. Crisp, “Presentism,” in Michael J. Loux & Dean W. Zimmerman (eds.), The Oxford Handbook of Metaphysics (Oxford Univ. Press, 2003), pp. 211–245; Craig Bourne, A Future for Presentism (Oxford Univ. Press, 2007).

Monday, November 15, 2010

Divine Eternity

This is the first of 17 posts that, collectively, defend Open Theism against Mawson’s Divine eternity (2008). As I write them, I shall be polishing up what I was writing over the summer, i.e. Eternity, Mawson’s belief and Cantor’s paradox, which was itself the result of a very slow revision of the first half of my 2008 reply to Mawson, Omniscience and the Odyssey Theodicy. The Abstract for the current paper is:
T. J. Mawson believes that the God of Open Theism is liable to bodge things up, by not infallibly knowing all about the future. But I argue that Mawson misconstrued the Open Theist view of divine action. And since the God of Presentist Open Theism ould infallibly know all there is to know, I also argue that Presentism, whose falsity Mawson presupposed, is not implausible if God is the Perfect Being. Furthermore, if God can create arbitrarily many things, then because of Cantor’s Paradox, His knowledge of whole numbers is plausibly growing forever. Yet even such a powerful and hence changing God could, under Presentism, know all the truths of arithmetic. I conclude that the Presentist Open God could be the Perfect Being.
According to T. J. Mawson [i], even those Perfect Being Theists who take a libertarian view of free will should reject Open Theism, so long as they accept what he calls “the reality of the future,” i.e. “that some statements concerning what is now the future are true.” [ii] Mawson argued that because of future contingents, the Open God lacks “infallible knowledge of at least some aspects of the future,” [iii] and that such incomplete omniscience makes “whatever goodness (in the sense of beneficence, not just benevolence) God has a matter of luck.” [iv] I will be uncovering several lacunae in Mawson’s reasoning (in sections III to V), and then arguing more directly (in sections VI to VIII) for my conclusion, that such Theists should not reject Open Theism. The underlying question concerns how God is eternal (sections I and II). The 16 posts will be:
............I Introduction
............II Divine Attributes
............II Divine Attributes cont.
............III Future Contingents
............III Future Contingents cont.
............IV Theistic Presentism
............IV Theistic Presentism cont.
............IV Theistic Presentism again
............V Bodging Up
............V Bodging Up cont.
............VI Possible Worlds
............VII Cantor’s Paradox
............VII Cantor’s Paradox cont.
............VII Cantor’s Paradox again
............VIII Omniscience Again
............VIII Omniscience Again cont....

......[i] T. J. Mawson, “Divine eternity,” International Journal for Philosophy of Religion 64 (2008): 35–50.
......[ii] Ibid, p. 37. Statements are basically possible assertions. For more details, see T. J. Mawson, Belief in God: An introduction to the philosophy of religion (Oxford Univ. Press, 2005), p. 239 n. 6. Questions of truth are essentially questions of how well our words describe the world, of course.
......[iii] Mawson, “Divine eternity,” p. 37.......[iv] Ibid, p. 49.

Saturday, November 13, 2010

The Alternative to Naturalism Philosophy, which revolves around debates between Naturalists and Theists. It is a few centuries since Philosophy was the alternative to Theism, but the mainstream of analytical philosophy remains Naturalism, which is essentially atheistic. Science, which Naturalists emphasise, is not atheistic, however, but agnostic. Indeed, the particular sciences are not just agnostic about God, but about most other things too, so that scientists make the most interesting connexions. But Naturalists, no less than Theists, aim not so much to join up the sciences, but to find holes in each others’ arguments.
......As a mathematician, I am quite interested in seeing how mathematics would differ from standard set theory were we created by a Perfect Being. Indeed, I suspect there is an argument from 2 + 2 = 4 to the existence of a Perfect Being who created us. Mainstream philosophy of mathematics takes ‘2 + 2 = 4’ to be what mainstream mathematics—whose foundation is axiomatic set theory—says it is, and aims to develop an atheistic epistemology of set theory. As they do so, their concepts become implausible (whence the possibility of such an argument).
......Ironically, it is because I am essentially a mathematician that my approach to philosophical problems would strike most analytical philosophers as insufficiently mathematical (formal). And incidentally, there is a famous story (quoted from blogcritics) that:
Czarina Catherine the Great of Russia was concerned about the deleterious effect the philosopher Diderot was having on the religious faith of the nobility who were listening to him hold forth on atheism in her court. She encouraged famous mathematician Leonard Euler to confront him, and he did, with the following challenge: “Sir, (a + bn)/z = x, hence God exists—reply!” Diderot, who, according to the story, was completely mystified by all things mathematical, fled the court and
Russia in deep humiliation. Diderot and Euler actually were in Russia at the same time, both at the invitation of the Czarina, but this is a joke at Diderot’s expense that neither Euler the man nor Euler the mathematician would have made. Even if it had been, Diderot—who was actually a fairly capable mathematician himself—would not have been stumped.