# 2008-9

September 24, 2008, 6-7:30 PM in 234 Moses Hall

*Frederick Eberhardt (Berkeley/Washington University)*

Learning from Experiments

Are human learners good at causal learning? Do they perform the right experiment or sequence of experiments? In fact, what is the right experiment or sequence of experiments, both for human and ideal computational agents? Toward answering these questions, I will present recent experimental work on human causal learning that builds on research in psychology and cognitive science, and I will then lay out a new normative theory of causal discovery. By approaching the problem from both the descriptive and the normative side, we get some traction on the problem of causal learning in general.

October 15, 2008, 6-7:30 PM in 234 Moses Hall

*Elain Landry (UC Davis)*

Reconstructing Hilbert to Construct Category-Theoretic Algebraic Structuralism

Recently Shapiro has used the Frege-Hilbert debate to argue that category theory cannot be used to frame the position of the algebraic structuralist. More generally, he argues that one cannot be a structuralist all the way down; either, like Frege, one is forced to accept the existence of an assertory background theory, or, like Hilbert, one is forced to appeal to “philosophy”. In this paper I argue that this dichotomy is false. One can rationally reconstruct the components (conceptual, logical and contentual) of Hilbert’s structuralism in a way that shows that one can be a structuralist all the way down. Using category-theory to then frame the position of the Hilbert-inspired algebraic structuralist, one can use the various category axioms to mathematically analyze the concepts of mathematics, one can use various categorical logics to logically analyze the “criterion of acceptability” for axiom systems themselves, and one can use various category-theoretic structures and methods to analyze the content (semantic, proof-theoretic, or finitistic) of mathematical reasoning itself. Thus, one need not appeal to either an assertory, meta-mathematical, background theory or to “philosophy”; one can use category theory itself to frame the position of the algebraic structuralist.

December 03, 2008, 6-7:30 PM in 234 Moses Hall

*Craig Callender (UCSD)*

What Makes Time Special?

What is the difference between time and space? This paper proposes a novel answer: the temporal direction is that direction on the manifold of events in which our best theories can tell the strongest, most informative “stories.” Put another way, time is that direction in which our theories can obtain as much determinism as possible. I make two arguments. The first is a general one based on an empiricist theory of laws. I argue that according to this theory time is distinguished as the direction of informative strength. The second argument is a more specific illustration of the first: understanding ‘strength’ as having a well-posed Cauchy problem, I show that for a wide class of equations the desire for strength does indeed distinguish the temporal direction. Not only that, but the argument rigorously connects three otherwise mysterious connections among temporal features to one another. The paper then explores the ramifications of this theory for various problems in the philosophy of time.

March 04, 2009, 6-7:30 PM in 234 Moses Hall

*Bas van Fraassen (San Francisco State University)*

Tracking Truth: the Possible Statistics

The criterion I propose for policies to manage our opinion is that they should not prevent our tracking the truth – to wit, that our subjective probabilities should be such as to possibly match an assignment of proportions (or long-run relative frequencies) in a (not necessarily conceivable) population. This criterion has bite, applied to various policies (proposed in the literature) for updating opinion in response to experience, under conditions that relate prior opinion to a wide range of types of new input. Much depends on how nature is put to the question.

March 18, 2009, 6-7:30 PM in 234 Moses Hall

*Edouard Machery (University of Pittsburgh)*

Experimental semantics (or what would Kripke have said if he were Asian?)

Theories of reference have been central to analytic philosophy, and two views, the descriptivist view of reference and the causal-historical view of reference, have dominated the field. In this research tradition, theories of reference are assessed by consulting one’s intuitions about the reference of terms in hypothetical situations. Particularly, in Naming and Necessity, Kripke developed some well-known thought-experiments that were widely taken to undermine descriptivist theories of reference. But what if the intuitions elicited by Kripke’s thought-experiments were not universal? What would be the implications for theories of reference if these intuitions varied across cultures? Machery et al. (2004) presented some evidence that Westerners and East Asians tend in fact to have different intuitions about reference, and they argued that these findings had puzzling philosophical implications. After a brief review of this early work, I will examine some recent objections by Devitt, Marti, Deutsch, and Ludwig and I will describe some additional research done in response to these objections.

April 15, 2009, 6-7:30 PM in 234 Moses Hall

*Isabelle Peschard (San Francisco State University)*

Data-model or artifact?: on the role of relevant parameters in constructing models of phenomena

May 13, 2009, 6-7:30 PM in 234 Moses Hall

*David Malament (UC Irvine)*

How Space Can Be (and Is) Finite

The goal of the talk is to clarify certain points about “space” and “spatial geometry” within the framework of general relativity. (Within that framework, talk about four-dimensional spacetime geometry is perfectly unambiguous, but not so talk about three-dimensional spatial geometry.) So, for example, consider this question: “How big was space just after the big bang.” It is a trick question because it depends on what one means by “space”. Indeed, if the universe is described by a standard Friedmann-Robertson-Walker cosmological model in which k = 0 or k = -1, then the answer is “infinitely large” in one sense of “space”, but “incredibly small” in another sense of “space”.