Archive: History of Philosophy
On bad anecdotes and good fun
My initial topic is the attractions of scandal, and an oft-told story: Diderot, humiliated at the court of Catherine by his inability to answer Euler’s supposed mathematical proof of the existence of God, limps back home to Paris.
The moral generally drawn from the story is: Learn your algebra! My moral will be an admonition to historians (but not only to historians).
I’ve read the Diderot anecdote many times—mathematicians seem to like it—and I’ve long been suspicious. Inspired by a colleague’s use of it in a talk last semester, I did some checking. Here’s what I found.
Past and present: two illusions
A recent NewAPPS post by Helen De Cruz and a not-so-recent post elsewhere by Eric Schwitzgebel will serve as hooks from which to hang some thoughts about two complementary illusions: the transparency of the present, the opacity of the past.
Helen, a lutenist, asks whether she can “ever claim to understand” the late sixteenth- and early seventeenth-century music she’s playing. There is a “gap”—a gap familiar to anyone who has undertaken to perform early music—between us and the works.
Schwitzgebel, on the other hand, is not much worried about our access to old texts.
Maybe empirically oriented philosophers typically don’t regard themselves as expert enough in history of philosophy to write about it. But I think we hobble ourselves if we allow ourselves to be intimidated. The standard of expertise for writing about Descartes or Kant in the context of a larger project — a project that isn’t just Descartes or Kant interpretation — shouldn’t be world leadership in Descartes or Kant interpretation. It should be the same standard of expertise as in writing about a contemporary colleague with a large body of influential work, like Dennett or Fodor.
In a way I agree with Schwitzgebel. A “world leader” in Descartes scholarship knows far more, in some respects, than you or I need to know in order to read the Meditations. But what exactly is the “standard of expertise” required in writing about one of our contemporaries?
Texts as pretexts, or: the practitioner’s attitude
Mohan Matthen has been commendably frank in expressing his attitude toward the history of philosophy. But in fact what he has expressed does not pertain to history in particular: it pertains to any source of inspiration. It is what you might call the practitioner’s attitude.
When one reads Julia Annas or Margaret Wilson or Michael Friedman one thinks: Gee that’s really interesting. Could Aristotle or Descartes or Kant really have thought that? […]
And then one thinks: Oh who cares? It’s so interesting that it’s worth tackling on its own. But, no doubt, it gives the question a certain beautiful frisson that Kant could have held it.
[From NewAPPS.] Nothing at all changes if you substitute ‘Susan Wolfe’ or ‘Mohan Matthen’ for ‘Aristotle’ or ‘Descartes’. For me as a practitioner it’s of no especial import to get Aristotle or Mohan right so long as I have arrived at something of interest to me. It may be that a historian has helped me along toward that end. But what matters is that I have been inspired, that I am having interesting thoughts.
To that end presumably whatever works is licit, so long as it is not morally objectionable. I could just as well as have consulted tea leaves. I am, so far as inspiration is concerned, a pure egoist, a solipsist even, since it hardly matters whether I have listened to you or merely dreamt of listening to you.
The attitude of the practitioner ought not to be given any weight, therefore, to in judging the worth of history. It is too indiscriminate. The practitioner is indifferent to anything that fails to inspire interesting thoughts, and will value anything that does, whatever its intrinsic worth.
The truth about infinitesimals
In what follows I am not pushing any conclusions; I’m offering an extended example with which to think about questions of truth and historical interpretation.
Russell knew how things stood with infinitesimals. Weierstrass and Cantor have solved the problem of placing the calculus on a rigorous basis. The infinitesimals of an earlier age are banished; the contradictions entailed by their use can now safely be ignored because it has been shown we can do without them. (NB: My guide in this discussion is John Bell’s The continuous and the infinitesimal, esp. ch. 4.)
Leibniz in particular is censured for having given a “wrong direction to speculation as to the Calculus”.
His belief in the actual infinitesimal hindered him from discovering that the calculus rests on the doctrine of limits, and made him regard his dx and dy as neither zero, nor finite, nor mathematical fictions, but as really representing the units to which, in his philosophy, infinite division was supposed to lead (Russell, The Principles of mathematics 325).
Leibniz’s—and his successors’—attempts to save infinitesimals were bound to come to naught, because “infinitesimals as explaining continuity must be regarded as unnecessary, erroneous, and self-contradictory” (Principles 345: his verdict on Hermann Cohen’s Neo-Kantian interpretation of the calculus).
Celebrating the accomplishments of Weierstrass, Russell makes his work a fulfillment of Zeno’s:
After two thousand years of continual refutation, these sophisms [Zeno’s paradoxes] were reinstated, and made the foundation of a mathematical renaissance, by a German professor, who probably never dreams of any connection between himself and Zeno. Weierstrass, by strictly banishing all infinitesimals, has at least shown that we live in an unchanging world, and that the arrow, at every moment of its flight, is truly at rest (347).
What Russell knows is that the key notion of the calculus—that of limit—has been defined by nineteenth-century mathematicians in terms that make no reference to other than “normal” finite quantities. In the classical ε, δ definition of convergence, those variables range over ordinary numbers like .01 or 1/π. The dx and dy of Leibniz’s calculus are thus eliminated; every proposition containing such symbols can be replaced, salve veritate and also salve deductive relations, by a proposition not containing them. Elimination by definition became a familiar strategy in analytic philosophy, carried forward in extremis by “nominalists” whose aim was to eliminate by similar means all abstracta, including the sets or classes to which, in the late nineteenth century, all other mathematical entities then conceived had been reduced. The model and origin of all such reductions was, directly or indirectly, that of Weierstrass.
The importance of that model would be difficult to exaggerate. It was seen to be the successful solution, ending all dispute, to a longstanding philosophical and mathematical problem, the problem of infinitesimals. It was Progress with a capital P.
Rightly termed, witcraft
Eric Schliesser’s note on translation put me in mind of one of my favorite books. Early in my graduate career I discovered in the Stanford stacks a series of reprints, mostly in English, from the sixteenth and seventeenth centuries, published by Scolar Press, now sadly defunct. Among the many wonderful facsimile volumes in the series was Ralph Lever’s The arte of reason, rightly termed, witcraft teaching a perfect way to argue and dispute (1573). This is said to be, after Thomas Wilson’s Rule of reason (1552), the second logic book written in the vernacular. And boy is it…
To give you a taste, here is an excerpt from the chapter which in our English would be entitled “Of the subjects and predicates that are in a simple proposition”. The “storehouses” are the categories of Aristotle; a “naysay” is a negation.
Of the foresets and back sets that are1 The foreset is a nowne placed afore the verbe, and the backset after, as, man is juste: man is the foreset, and just, is the backeset.
in a simple shewesaye. Chap. 3.
in a simple shewesaye. Chap. 3.
2 Sometymes a whole sentence or a clause of a sentence is a backset, or a foreset: as to rise earely is a holesome thing: in this shewsay, to rise earely, is the foreset, and a holesome thing is the backsette, they both supplying the roome and office of an nowne.
To what use foresettes and backesettes serve.3 The storehouses serve to shew the nature of wordes as they are taken and considered by themselves alone.
4 The foreset & backset of a shewsay declare the respecte that wordes have one to [71|72] an other, as they are coupled and linked together in a perfect saying.
To knowe what respecte the backset hath to the foreset5 If the backset is deuided and parted a sunder from the foreset by a naysay, then doth it but eyther differ from it, or els it is a gainset to it.
in every simple shewsaye of the seconde order.
in every simple shewsaye of the seconde order.
6 What differing words and gaynsets are, we have shewed afore in the. 12. Chapter of the first booke.
7 If it be affirmed & coupled to the foreset by a yeasay: then muste the foreset and backset be such as either may be saide of other turne for turne, or not saide.
8 If either may be said of other turne for turne, then is the one of them the kindred, and the other his saywhat: or els one the kindred and the other his propertie.
9 For onelye the saywhat and the propertie compared to the kindred, maye bee said of it, and it of them, turne for turne: but the saywhat expresseth what the kindred [72|73] is, and the propretie doth not.
Lever was very deliberate in his coining of terms; the new terms are intended to replace the Latin-derived terms hitherto in use, to the advantage of those “english men” not versed in the Classical languages. There is no question but that English is up to the task of teaching logic; the only problem will be that some new words will have to be used.
More of the same
[From NewAPPS]. Eric Schliesser has recently mentioned a conference on self-plagiarism, inspired, apparently, by Bruno Frey’s republication of the same article in more than one venue. That act of self-plagiarism reminded me of the notion of “plagiat par anticipation”, which in its simplest form is the act of appropriating, without acknowledgment, the work of one’s successors. The notion was introduced by Francois Le Lionnais, one of the founders of Oulipo, in a flagrant plagiat par anticipation of Pierre Bayard’s book on the subject forty years later.
Gérard Genette somewhere (in Palimpsestes?) introduces the more elaborate notion of “auto-plagiat par anticipation”, which is to say the act of anticipating or drawing upon one’s own future works. So perhaps Bruno Frey was just making good his earlier acts of self-appropriation.
In a passage that I think Eric will appreciate, Aurélien Rouquet [pdf], who unfortunately has not managed a plagiat par anticipation of Bayard, and is therefore forced servilely to write about him, says:
La première thèse est celle d’une « histoire littéraire autonome ». Précisément, Bayard appelle « à séparer une fois pour toute l’histoire événementielle et l’histoire littéraire, et à admettre que les écrivains et les artistes relèvent en réalité d’une double chronologie » (p108). Prenant acte des similitudes que l’on ne manquera jamais de trouver entre écrivains éloignés dans le temps (du fait de l’existence du plagiat par anticipation), Bayard propose ainsi de narrer l’histoire littéraire sur la base de ces similitudes, plutôt que sur le fait que certains écrivains ont pu vivre à une même époque. Selon lui, il n’y aurait pas scandale à présenter Sophocle, qui a narré le mythe d’Œdipe en utilisant une technique tardivement utilisée au sein de la littérature policière (le meurtrier est l’enquêteur), au côté de Freud et d’écrivains du 20e siècle.
Translation: The first thesis is that of an “autonomous literary history”. Bayard calls for a “separation once and for all of event-history from literary history”, and for an “admission that literature and art are referred to a double chronology”. Taking note of the similarities one will never fail to find between authors far apart in time (on the basis of plagiarism by anticipation), Bayard proposes to narrate the history of literature on the basis of those similarities, rather than on the basis of the fact that certain writers happened to live in the same period. There would be no scandal in presenting Sophocles, who told the myth of Œdipus using a technique later employed in murder mysteries (the murderer is also the investigator), alongside Freud and other twentieth-century authors.
As Bayard knows, he has been plagiarized in advance by Borges, who wrote of a literary history in which Kafka, rather than being influenced by his precursors, creates them (“Kafka and his precursors”, in Other inquisitions).
Behind these jokes there can be discerned a serious issue for the historian. In the sixties it was discussed under the heading of “genesis and structure” (Piaget, Derrida), but I will use the more familiar terminology (for anglophone philosophers) of types and events. The historian, even in bare narrative, cannot merely order events by time; some principle of selection is needed on the basis of which some subset of “all” the events within some period (the object of an ideal, impossible, “total” history) is selected. Those events will be of a type which is itself perhaps limited in time and space (e.g. “Baroque”), but whose conditions of existence in time will differ from those of the events falling under it. Considered as instances of the type, the events stand in a timeless relation of similarity, and could be re-ordered without ceasing to stand in that relation. That is, of course, what Borges suggests: the “precursor” relation, insofar as it based upon similarity, is reversible.
Feyerabend: heathen, yes, anti-science, no, at least not until Farewell to Reason (but really what he opposed was the employment or diversion of science to authoritarian, anti-democratic ends: invoking “expertise” so as to shut off debate and exclude “laypeople” from decision-making). Certainly not a nut-job; he disliked academic stuffiness and professorial anxieties about respectability and stuck many a pin in many an inflated ego (read “New Clothes from the Emperor’s Bargain Basement” to see him take apart Larry Laudan).
I once read all of the reviews of Against Method I could find. Very few of them took the trouble to understand his arguments. They mostly got stuck at his announced “anarchism” and the slogan “anything goes”, and thereupon stopped reading. Feyerabend quite understandably became angry at his treatment by the reviewers. Admittedly he was given to boxing the ears of those he thought were deliberately obtuse, but he also with some care reiterated the points he thought they had missed.
Professional philosophy has since his heyday gotten even more stuffy and respectable. I can’t think of a single figure who even begins to approach Feyerabend (or crazy old Popper, for that matter, the High Priest of Objectivity from whom F. and several other well-known philosophers of science were apostates) in their willingness to question everything rather than sticking safely to some well-trodden terrain of “problems” and “solutions”.
On contingency in history
ES: Daston’s response to this situation is to promote an agenda to chart the growth and transmutation of reason and the accompanying techniques and epistemic virtues through the ages. (One sees some of this in her book with Galison on objectivity.) While this (Foucault-lite genealogy) is certainly a philosophic project in so far as philosophy is the science that also reflects on itself and its (historical) presuppositions (one can say that reason is partial without historical self-understanding), the philosophy to be found here is skin-deep. Its results will provide a lot of information, and, perhaps, a healthy skepticism about the nature and sources of science’s self-image.
But it lacks philosophic ambition because it has fully embraced the cult of contingency. It can’t even bring itself to use this historical knowledge to ask what the necessary conceptual, social, mathematical or technical pre-conditions are or may be for the way (scientific) reason develops in society. That project, first hinted at by David Hume (in his treatment of justice) and widened by Adam Smith, Hegel, and Marx, was revived and transformed by the early Foucault in The Order of Things (original title: Les Mots et les choses), while Kuhn, Popper, Feyerabend, and Lakatos were having their epic debates during the 1960s. The problem with Foucault’s archeology is that he never appears to have seriously engaged with the citadel of science: physics. Now a half century later there appear to be few ambitious historically informed projects left.
“Cult of contingency” [a phrase used by ES to denote the position he opposes] is a nice bit of rhetorical icing. But where’s the cake? In response to comments pointing out that some historians regard their work as having provided evidence for contingency, you reply that their methods make it impossible to see anything but contingency.
The structure of your argument so far is: those who hold that the history of science exhibits no regularities (that, I gather, is what you mean by the “contingency” part of “cult of contingency”; you seem to agree that no-one has discovered “laws of development” in the history of science: but in your view there are or may be regularities of some weaker sort?) do not have sufficient evidence for their claim because they have not looked for evidence for the counterclaim that there are regularities.
Whether that is deserving of the propaganda label “cult”, I don’t know. Sounds like garden-variety confirmation bias to me. (How many providentialist historians devoted serious effort to disproving contrary hypotheses?) I suspect the original impetus behind the predilection for contingency that many historians of science do exhibit was owing to a reaction against presentist progressivist history (rather than against Marxist theories of history, say). Writing the history of old science as the slow but inevitable march from darkness and ignorance to our present condition of enlightenment and knowledge resulted quite often in lousy history.
I agree that to force a choice between historical laws and mere chance is fallacious. But it seems to be very difficult to find grounds—even when you do look for them (and I think you need a lot more evidence to support your claim that people have not)—to deny contingency over the long run, because events like the publication of The Origin of Species depend on a whole host of earlier developments such that if you remove one or some of them, it’s not at all clear what “would” have happened subsequently.
Imagine 18th-century natural history in the absence of discoveries from the New World, Asia, and Africa; consider whether Darwin would have had models for the transformation of species had there not already been a lot of thinking about “development” in the late 18th and early 19th century, in cosmology and geology especially; or to what degree his evidence-gathering relied upon extensive worldwide networks of correspondence such that the existence of the technologies supporting then was contingent with respect to the character of biological thought in the period.
In short: changes in the sciences (and a fortiori in philosophy) tend to depend on complexes of active causes (e.g. the agencies behind the Human Genome Project) and causal conditions (knowledge concerning polymerase chain reactions?) that seem to be contingent (or “chance” in the Aristotelian sense of logically contingent meetings of causal sequences which taken in themselves are owing to the natures of the objects involved in them, and are therefore not “chance”). That, and not some supposed “cult of contingency”, would be the grounds for denying that strong global regularities are likely to be found in the history of science (or philosophy: but perhaps philosophy is a special case? if so, how?).
ES: “I am not against the claim that history is contingent; I am against a methodology that enshrines contingency into its ideological core, so that very different understandings (note the plural) of history are ruled out in advance. (Ones in which history has a meaning, a function, a political craft, a regulative ideal, etc.)”.
It seems to me that several quite different issues are conflated here. One is whether history—i.e. the past, considered as the object of the discipline of history—is contingent, i.e. devoid of regularities of its own (that is, not already belonging to psychology, biology, etc.). That is a matter to be settled by the evidence. Does science do better in free-market societies? How are scientific disputes brought to an end—by crucial experiments, or what? Those are perfectly sensible empirical questions. [Added here: And if they were answered in the affirmative, then the history of science would have regularities of its own.]
Another is whether there are long-term narrative “arcs” in the history of science or the history of philosophy. I think there are, but I think it takes tremendous work to (i) formulate reasonable claims while
In an ideal world I would be working on a long-term arc concerning authority and authorities—the breakdown of the system we see in the late Middle Ages and even into the early seventeenth century, a system in which each discipline was based around a few authoritative texts, teaching took the form of commentary on those texts, and innovation occurred within what was ostensibly an exposition or extension of authoritative, authorized opinion; followed by a sort of interregnum (the 17th century, more or less), followed by a reconstitution of authority. That’s an arc that, if I included some account of the rise of the older system (taking off from H. I. Marrou and others on knowledge-systems in antiquity), would extend over 1500 years or more. It wouldn’t be a story of progress, necessarily; nor do I know in advance whether the succession of systems of authority has an explanation of the sort that would exhibit it as other than contingent—as perhaps a progression rather than a mere succession. It doesn’t seem to me that I’m ruling that out. (Or that in Physiologia I was ruling out the insertion of its story into some larger story about the rise of modern science. But I did want to make that larger story harder, or ideally impossible, to tell without taking late Scholasticism seriously, which does eliminate certain triumphalist narratives resting largely upon ignorance of those sources.)(ii) avoiding partiality and the “déformations professionelles” that result from knowing some sciences better than others, and (iii) satisfying that good old Hempelian total evidence requirement.
A third issue concerns the function of historical narratives (I think we can agree that the history we have in mind is mostly narrative history, which by its form alone—even if you don’t go so far as Hayden White—is already conducive to attributing intentionality or purposiveness to historical change). History as political craft, I take it, would be a sort of Mirror for Magistrates: it would use accounts of the past as a basis for practical advice. Nothing wrong with that.
History as a regulative ideal? I don’t know what you mean, unless you’re thinking of e.g. the progress of humanity toward universal peace as a sort of lens through which to examine historical change. History as propaganda, I suppose, is what it amounts to: the sort of reading that certain Christians engage in to show that the eschatology of Revelations has been realized through the ages and is being realized in the present. I have my doubts as to whether historians of that sort are likely to satisfy the rather strict requirements you place on the contingentists: are they required to refute contrary hypotheses too? I don’t deny that good history—and perhaps the most memorable sort of history—can be written under the guidance of an ideal; but I’m not sure that we need more of it.
A Janus-faced discipline
If the history of philosophy needs defending, the posts listed above ought to persuade anyone persuasible. Rather than add another log to the palisade, I thought it would be useful to try to understand why the question keeps coming up.
There’s ample evidence that it does come up every so often. You’ll find earlier stages of the discussion in Margaret Wilson’s Descartes, in Bernard Williams’ introduction to his Descartes (and the afterthoughts in A Sense of the past), in Alan Gabbey’s “Arguing with the ungrateful dead”—I can’t find a reference to it, but it circulated in samizdat in the late 1980s—, and the introduction to Dan Garber’s Descartes embodied.
It keeps coming up, I think, because the history of philosophy has two faces. One looks toward intellectual history, itself a branch of cultural history, and the other toward contemporary philosophy. Call these the East Face and the West Face (that gives me room for two more if I need them…). The East Face thinks of philosophical texts in the manner of a historian: they are remains of the past which happen to be available to us in the Archive (see Foucault’s Archeology), and which we take as indices of past events, notably the acts of thought we take to be evidenced by the texts we study. The task of the intellectual historian (once the basic work of putting together the Archive is done) is to describe accurately and to explain those events.
Putting together the Archive is itself a very difficult and challenging task—see Thomas Tanselle’s work on editing and textual criticism; or take a look at André Robinet’s edition of Leibniz’s Principes de la nature et de la grâce.That’s a rather atmospheric way of saying that we look at texts, try to determine the intentions behind the speech acts of their authors, and—having thus understood the phenomena—try to understand why the authors did what they did. The process goes on at the level of phrases (e.g. Descartes’ semel in vita), arguments, whole texts, œuvres, schools. In my view every responsible reader does history, at least occasionally. Only in those situations in which everyone understands everyone else so well that “hitches” in understanding—do you mean by ‘essence’ what I mean?—never get in the way will we not be engaged in tasks resembling those of the historian properly speaking.
Consider the giants of the 50s—Quine, Carnap… For today’s graduate student, I suspect, a great deal more needs to be motivated and explicated than when I first encountered them; in the 70s there were plenty of native Quineans and Carnapians from whom one could absorb the requisite understandings without having to crack a book.
Nothing in that task involves knowledge of or reference to contemporary discussions of the “same” questions or concepts. Indeed it is often better to bracket what you know about the state of the art now so as to avoid anachronism. The historian of Renaissance perspective may find it pedagogically useful to refer to projective geometry (whose roots lie in the thinking of Desargues and others on the foundations of perspective drawing), but neither that nor, say, acquaintance with 20th-century “post-perspective” painting will assist the task of description and explanation—except obliquely, by contrast for example (perhaps a historian now understands the significance of perspective better now that it is no longer taken for granted; in this way the present serves the same purpose as any other contrasting period would serve).
On the difference of humans from animals and the difference it makes
This is a response to a post on Justin Erik Halldór Smith by the philosopher of that name, and containing comments by Abraham Stone and Frans de Waal. You might well want to read that first before reading this.
The problematic here can be found already in Spinoza and Bayle. It can be resolved into two challenges to the person who holds that there is a profound difference, in the moral sphere, between humans and animals. The first challenge is to exhibit a difference between humans and every other species of living thing that is not a mere matter of degree; the second is to show that that difference has moral significance, e.g. that on its basis we have duties toward humans that we don’t have toward animals. I’m not sure even the first challenge can be met, let alone the second.
Every time I read Spinoza I’m troubled by the lack of motivation for his claim that humans can treat animals as we please (subject to their “natural right” against us, which is nothing more than their power to resist or overcome us).
His account of the difference is that it is a matter of complexity; but complexity is a matter of degree; it is, moreover, not easily seen to be of moral significance, and certainly not to the degree required for the contrast Spinoza draws. I think Abe is on the right track when he says that the main motivation for making the possession of reason an all-or-nothing affair is to build as high a wall as possible between us and the rest of the living world; and if even so vernunftgetrunkenen a philosopher as Spinoza gets swept away by prejudice, then clearly something powerful lies behind it.
The best one can do on Spinoza’s behalf, I think, is to take it that in the Part 4 conception of morality the only basis other than power for rights (or rather for justice) is the Hobbesian state, which requires the capacity to understand and enter into contracts. Only humans, it would seem, have this capacity, and so only humans fall within the scope of justice. It’s still not easy to see how this squares with the physiological notions of Part 2, but at least the criterion is not arbitrary, and not a matter simply of our having more power. (As for the good of Part 5, the eternal love of God, that would seem to be accessible to every individual to the limit of its capacities for adequate knowledge.)
Taking this into the present, the evidence now favors the claim that intelligence is a matter of degree—except for the matter of language use. But here two additional issues would need to be addressed: whether the capacity to use language is an indissoluble, all-or-nothing capacity and whether the appearance of a discontinuity between us and the rest of the animal kingdom isn’t perhaps an artifact of the extinction of other hominids intermediate in capacity between us and surviving primates. If there are stages or degrees in language-acquisition, some of which are already present in extant species, and a full spectrum of which would have been instantiated in our hominid relatives, then in order to make “the” capacity to use language decisive you would have to explain why the precise version of it possessed by humans, or rather why the difference between that version and the others, should have moral significance. I myself don’t see much hope of that.
I think the point about our comprehension of one another as human is well taken (JS: “The only reason why we don't have any problem attributing intelligence to other human minds is that we need to suppose their existence on practical grounds”). I would add that humans who are not prepossessed by the thought that there is some deep metaphysical divide between us and the rest of the living world, though they of course distinguish themselves from other species, often regard animals as having minds. The “theory of mind” is not restricted to humans. We model them as childlike, as dependent, in part because in human society they are dependent, in part because like children they don’t have all the capacities or knowledge of adult humans. Nevertheless domestic animals, the ones we live with for years, and whom we get to know as individuals, have a sort of moral standing; and if that is thought to be some sort of invention, then I need to have shown to me the grounds upon which our attribution of moral standing to each other is not.