Scary news from Australia:
• Marc Rigby, Insect population decline leaves Australian scientists scratching for solutions, ABC Far North, 23 February 2018. I’ll quote the start:
A global crash in insect populations has found its way to Australia, with entomologists across the country reporting lower than average numbers of wild insects. …
Richard Rowlands' forthcoming Analysis paper on 'The Intelligibility of Moral Intransigence' presents a curious argument against moral cognitivism. It goes roughly as follows:
P1. Beliefs track perceived evidence. …
‘Socrates is a philosopher’ gets rendered into an appropriate formal language of predicate logic by the likes of ; ‘Someone is a philosopher’ gets rendered by . The syntactic difference between a formal name and a quantifier-tied-to-a-variable vividly marks a semantic difference between the rules for interpreting the two resulting formal wffs. …
Atomic sentences – or the propositions they express – can be true, as can logically complex sentences composed out of atomic sentences. A comprehensive metaphysics of truth aims to tell us, in an informative way, what the truth of any sentence whatsoever consists in, be it atomic or complex. Monists about truth are committed to truth always consisting in the same thing, no matter which sentence you consider. Pluralists about truth think that the nature of truth is different for different sets of sentences. The received view seems to be that logically complex sentences – and indeed logic itself – somehow impose a monistic constraint on any comprehensive metaphysics of truth. In what follows, I argue that the received view is mistaken.
We often find ourselves in disagreement with others. You may think
nuclear energy is so volatile that no nuclear energy plants should be
built anytime soon. But you are aware that there are many people who
disagree with you on that very question. You disagree with your sister
regarding the location of the piano in your childhood home, with you
thinking it was in the primary living area and her thinking it was in
the small den. You and many others believe Jesus Christ rose from the
dead; millions of others disagree. It seems that awareness of disagreement can, at least in many cases,
supply one with a powerful reason to think that one’s belief is
Causalists and Evidentialists can agree about the right course of action in an (apparent) Newcomb problem, if the causal facts are not as initially they seem. If declining $1,000 causes the Predictor to have placed $1m in the opaque box, CDT agrees with EDT that one-boxing is rational. This creates a difficulty for Causalists. We explain the problem with reference to Dummett’s work on backward causation and Lewis’s on chance and crystal balls. We show that the possibility that the causal facts might be properly judged to be non-standard in Newcomb problems leads to a dilemma for Causalism. One horn embraces a subjectivist understanding of causation, in a sense analogous to Lewis’s own subjectivist conception of objective chance. In this case the analogy with chance reveals a terminological choice point, such that either (i) CDT is completely reconciled with EDT, or (ii) EDT takes precedence in the cases in which the two theories give different recommendations. The other horn of the dilemma rejects subjectivism, but now the analogy with chance suggests that it is simply mysterious why causation so construed should constrain rational action.
This continues my previous post: “Can’t take the fiducial out of Fisher…” in recognition of Fisher’s birthday, February 17. I supply a few more intriguing articles you may find enlightening to read and/or reread on a Saturday night
Move up 20 years to the famous 1955/56 exchange between Fisher and Neyman. …
Hardin’s (1988) empirically-grounded argument for color eliminativism has defined the color realism debate for the last thirty years. By Hardin’s own estimation, phenomenal structure – the unique/binary hue distinction in particular – poses the greatest problem for color realism. Examination of relevant empirical findings shows that claims about the unique hues which play a central role in the argument from phenomenal structure should be rejected. Chiefly, contrary to widespread belief amongst philosophers and scientists, the unique hues do not play a fundamental role in determining all color appearances. Among the consequences of this result is that greater attention should be paid to certain proposals for putting the structure of phenomenal color into principled correspondence with surface reflectance properties. While color realism is not fully vindicated, it has much greater empirical plausibility than previously thought.
Here's a familiar puzzle: David Lewis was a better philosopher than me, and certainly knew more and had thought more carefully about issues surrounding the metaphysics of modality. He concluded that modal realism was true: that every concrete way that a world could be is a way that some concrete universe truly is (and that these concrete universes serve to ground modal truths -- truths about what is or is not possible). …
In two recent posts (here and here), I made arguments based on the idea that wobbliness in priors translates to wobbliness in posteriors. The posts while mathematically correct neglect an epistemologically important fact: a wobble in a prior may be offset be a countervailing wobble in a Bayes’ factor, resulting in a steady posterior. …
In particular, there has been a temptation to treat (1)-(3) as equivalent, to treat (4) and (5) as equivalent, and to suppose that each of (4) and (5) entails any of (1)-(3). There has been considerable controversy about whether this last entailment always holds. Ordinary subjects may judge that (4) and (5) are appropriate in cases in which none of (1)-(3) are—cases in which Jack’s breaking the base is a foreseen but undesired consequence of Jack’s intentionally doing something else. It is currently debated what the best explanation of such ordinary reactions might be. It is also debated what to make of the fact that ordinary judgments using the adjective intentional or the adverb intentionally seem influenced by normative considerations.
I propose a division of the literature on natural kinds into metaphysical worries, semantic worries, and methodological worries. I argue that the latter set of worries, which concern how classification influences scientific practices, should occupy centre stage in philosophy of science discussions about natural kinds. I apply this methodological framework to the problems of classifying chemical species and nanomaterials. I show that classification in nanoscience differs from classification in chemistry because the latter relies heavily on compositional identity, whereas the former must consider additional properties, namely, size, shape, and surface chemistry. I use this difference to argue for a scale-dependent theory of scientific classification.
Shagrir () and Sprevak () explore the apparent necessity of representation for the individuation of digits (and processors) in computational systems. I will first offer a response to Sprevak’s argument that does not mention Shagrir’s original formulation, which was more complex. I then extend my initial response to cover Shagrir’s argument, thus demonstrating that it is possible to individuate digits in non-representational computing mechanisms. I also consider the implications that the non-representational individuation of digits would have for the broader theory of computing mechanisms.
‘Modus Darwin’ is the name given by Elliott Sober to a form of argument that he attributes to Darwin in the Origin of Species, and to subsequent evolutionary biologists who have reasoned in the same way. In short, the argument form goes: similarity, ergo common ancestry. In this article, I review and critique Sober’s analysis of Darwin’s reasoning. I argue that modus Darwin has serious limitations that make the argument form unsuitable for supporting Darwin’s conclusions, and that Darwin did not reason in this way.
This paper gives a definition of self-reference on the basis of the dependence relation given by Leitgeb (2005), and the dependence digraph by Beringer & Schindler (2015). Unlike the usual discussion about self-reference of paradoxes centering around Yablo’s paradox and its variants, I focus on the paradoxes of finitary characteristic, which are given again by use of Leitgeb’s dependence relation. They are called ‘locally finite paradoxes’, satisfying that any sentence in these paradoxes can depend on finitely many sentences. I prove that all locally finite paradoxes are self-referential in the sense that there is a directed cycle in their dependence digraphs. This paper also studies the ‘circularity dependence’ of paradoxes, which was introduced by Hsiung (2014). I prove that the locally finite paradoxes have circularity dependence in the sense that they are paradoxical only in the digraph containing a proper cycle. The proofs of the two results are based directly on Konig’s infinity lemma. In contrast, this paper also shows that Yablo’s paradox and its ∀∃-unwinding variant are non-self-referential, and neither McGee’s paradox nor the ω-cycle liar has circularity dependence.
When scientists seek further confirmation of their results, they often attempt to duplicate the results using diverse means. To the extent that they are successful in doing so, their results are said to be ‘robust’. This article investigates the logic of such ‘robustness analysis’ (RA). The most important and challenging question an account of RA can answer is what sense of evidential diversity is involved in RAs. I argue that prevailing formal explications of such diversity are unsatisfactory. I propose a unified, explanatory account of diversity in RAs. The resulting account is, I argue, truer to actual cases of RA in science; moreover, this account affords us a helpful new foothold on the logic undergirding RAs.
Ruetsche () claims that an abstract C*-algebra of observables will not contain all of the physically significant observables for a quantum system with infinitely many degrees of freedom. This would signal that in addition to the abstract algebra, one must use Hilbert space representations for some purposes. I argue to the contrary that there is a way to recover all of the physically significant observables by purely algebraic methods.
The existence of non-standard models of arithmetic makes defining finitude problematic. A finite set is normally defined as one that can be numbered by a natural number, but what is a natural number? The Peano axioms sadly underdetermine the answer: there are non-standard models. …
For simplicity, most of the literature introduces the concept of definitional equivalence only to languages with disjoint signatures. In a recent paper, Barrett and Halvorson introduce a straightforward generalization to languages with non-disjoint signatures and they show that their generalization is not equivalent to intertranslatability in general. In this paper, we show that their generalization is not transitive and hence it is not an equivalence relation. Then we introduce the Andr´eka and N´emeti generalization as one of the many equivalent formulations for languages with disjoint signatures. We show that the Andr´eka–N´emeti generalization is the smallest equivalence relation containing the Barrett–Halvorson generalization and it is equivalent to intertranslatability even for languages with non-disjoint signatures. Finally, we investigate which definitions for definitional equivalences remain equivalent when we generalize them for theories with non-disjoint signatures.
Here’s a problem for Bayesianism and/or our rationality that I am not sure what exactly to do about. Take a proposition that we are now pretty confident of, but which was highly counterintuitive so our priors were tiny. …
Symmetry plays a number of central roles in modern physics. As the physicist Paul Anderson famously remarked, “it is only slightly overstating the case to say that physics is the study of symmetry” (1972, p. 394). Here I discuss just one role of symmetry: its use as a guide to superfluous structure, with a particular eye on its application to metaphysics. What is symmetry? Generally speaking, a symmetry is an operation that leaves its object unchanged in a certain respect. Rotation by 90 degrees is a symmetry of a square piece of paper, insofar as the paper’s extension through space is the same after the rotation as before. But we will focus on symmetries of physical theories, not paper. Roughly speaking, these are operations on possible physical systems that leave some aspect of the theory unchanged. Which aspect? That depends: different symmetries preserve different aspects. But an important class of symmetries are those that leave the dynamical laws of the theory unchanged; these are known as dynamical symmetries.
The idea that the world is structured—that some things are “built” out of others—has been at the forefront of recent metaphysics. Making Things Up presents a comprehensive and distinctive view on these matters. It is a model of good philosophy: ambitious, insightful, open-minded, and guided by sound judgment. Don’t be deceived by its conversational tone. The book contains riches on the surface and below; new layers are revealed with each reading.
Here’s a cool way to cut carbon emissions: a double conference. The idea is to have a conference in two faraway locations connected by live video stream, to reduce the amount of long-distance travel! Even better, it’s about a great subject:
• Higher algebra and mathematical physics, August 13–17, 2018, Perimeter Institute, Waterloo, Canada, and Max Planck Institute for Mathematics, Bonn, Germany. …
R.A. Fisher: February 17, 1890 – July 29, 1962
Continuing with posts in recognition of R.A. Fisher’s birthday, I post one from a couple of years ago on a topic that had previously not been discussed on this blog: Fisher’s fiducial probability. …
Phenotypic flexibility includes systems such as individual learning, social learning, and the adaptive immune system. Since the evolution of genes by natural selection is a relatively slow process, mechanisms of phenotypic flexibility are evolved to adapt to contingencies on the time scales ranging
Lots of new stuff in the Open Logic repository! I’m teaching modal logic this term, and my ambitious goal is to have, by the end of term or soon thereafter, another nicely organized and typeset open textbook on modal logic. …
Bayesian reasoning starts with prior probabilities and gathers evidence that leads to posterior probabilities. It is occasionally said that prior probabilities do not matter much, because they wash out as evidence comes in. …
(with Jonathan E. Ellis; originally appeared at the Imperfect Cognitions blog)
Last week we argued that your intelligence, vigilance, and academic expertise very likely doesn't do much to protect you from the normal human tendency towards rationalization – that is, from the tendency to engage in biased patterns of reasoning aimed at justifying conclusions to which you are attracted for selfish or other epistemically irrelevant reasons – and that, in fact, you may be more susceptible to rationalization than the rest of the population. …
Moral psychology and criminal jurisprudence share several important concepts, such as responsibility, excuse, blame, and punishment. Even if these shared concepts play somewhat different roles in these two domains, there is clearly significant overlap in their nature and demands. In fact, given the importance of moral ideas to the formation and reform of criminal law principles and practices and the effect of well-settled criminal law doctrine on our moral assumptions and beliefs, we should expect mutual influence and interaction between these domains. Culpability is one concept shared by moral psychology and criminal jurisprudence. But while culpability is a concept recognized in moral philosophy, it is deployed more regularly within the criminal law. Culpability plays an important role in the criminal law and in a broadly retributive justification of punishment, which understands the desert basis of criminal censure and sanction to consist in culpable wrongdoing. However, culpability is not a unitary concept in the criminal law. We can and should distinguish three different kinds of culpability within a retributive criminal jurisprudence.
(with Jonathan E. Ellis; originally appeared at the Imperfect Cognitions blog)
We’ve all been there. You’re arguing with someone – about politics, or a policy at work, or about whose turn it is to do the dishes – and they keep finding all kinds of self-serving justifications for their view. …