Metaphysics of Science
Warsztaty odbędą się w sali 205 w Starym Gmachu BUW / The Workshop will take place at Old Library Building at Krakowskie Przedmieście 24/26, room 205
Thursday 28th January 2009
14:15 – 15:30 Jan Hauska, “Invincible Dispositions”
15:30 – 16:30 Emma Tobin (University of Bristol)
“On the Identity of Dispositional and Categorical Properties”
17:00 – 18:00 Alexander Bird (University of Bristol)
“Time and Background-Free Theories”
Friday 29th January 2009
10:00 – 11:15 Stephen Mumford (University of Nottingham)
“Counterfactuals, Preventions and Absences”
11:45 – 12:45 Leszek Wronski (UJ)
“Causal Completeness and Completability in Classical Probability Spaces”
12:45 – 14:15 Lunch break
14:15 – 15:15 Tomasz Bigaj (UW)
“Ungrounded dispositions in quantum mechanics”
15: 45 – 16:45 Markus Schrenk (University of Nottingham)
“Resisting Metaphysical Necessity”
16:45 – 18:15 Stathis Psillos (University of Athens)
“Mechanisms sans Metaphysics”
TIME AND BACKGROUND-FREE THEORIES
In this paper I wish to begin to explore the consequences for metaphysics of thinking that a good physical theory should be background-independent. More generally I want to ask whether the conception of time not as a background but as an active component of the physical universe has any significant consequences for metaphysics.
A number of arguments have recently been offered in support of the thesis that
dispositional properties at the fundamental level are not susceptible to finks. I comment on one of them (ZNature’s Metaphysics, pp. 60-2), suggest another one, and contend that some fundamental dispositions are immune not only to finks but also to masks.
MECHANISM SANS METAPHYSICS
There have been two broad conceptions of causation. The first conception of causation, which may be called dependence or successionist, takes it that causation is a relation between two externally related events and is such that the cause is robustly related to the effect. The second conception, which may be called productive or generative, takes it that causation is a relation between two internally connected events and is such that the cause produces or generates the effect. There are several ways to unpack the idea of causation as a productive or generative relation, but the most prominent one (and, ultimately, the common factor in all ways) is that cause and effect are related by a mechanism, which is such that on being stimulated by the cause, it generates the effect. In this paper, I will examine several varieties of the mechanistic approach to causation in light of three plausible desiderata:
Plausibility (a plausible account should be given of how the cause produces the effect)
Generality (the causal connection should be generalisable: it should obtain in all kinds of domain)
Autonomy (higher-level causation should have some kind of autonomy; it should not be parasitic on causation at the physical level)
It will be argued that none of the traditional mechanistic approaches to causation satisfies jointly all three desiderata. Then, attention will be given to recent dualistic conceptions of mechanisms, advanced by Machamer, Darden and Craver, as well as to monistic conceptions, advocated by Glennan. It will be claimed that they too fail to satisfy the foregoing desiderata and that they generate different but important metaphysical commitments—the MDC approach to brute powers and the Glenna approach to non-mechanical laws. These problems will be alleviated if we leave the metaphysics of mechanisms behind and think of mechanisms purely in methodological terms.
“RESISTING METAPHYSICAL NECESSITY”
Our intuition that there is a de re connection in nature has one source in the felt resistance of the world against our wilful actions: I can’t lift this heavy weight, run 10k in under 40min, walk through this wall, etc.
Under Hume’s spell, who has denied that this intuition is veridical, even anti-Humeans have neglect this source and they focus entirely on a route against Hume that leads via Kripkean considerations. As a consequence, the link in nature that is widely accepted amongst anti-Humeans — metaphysical necessity — shares features of semantic, logical, apriori, analytic necessity.
In this paper I indicate that, because of these mentioned features, the Kripkean route is a doubtful way to the wanted de re connection in nature and that the first mentioned path — via the felt resistance of the world against our wilful actions — is more promising after all.
ON THE IDENTITY OF DISPOSITIONAL AND CATEGORICAL PROPERTIES
Strawson (2008) argues that there is no real distinction between an object’s categorical properties and its dispositional or power properties. He argues for this on the basis that if there were a real distinction between them, then they would have to be separable, and thus, must be capable of existing without each other. If the two properties are inseparable then they are numerically identical. Thus, there is no real distinction between the two. Pace Strawson, Oderberg (2009) argues that essence rather than identity grounds inseparability. This paper addresses other arguments for the non-identity of dispositional and categorical arguments.
CAUSAL COMPLETENESS AND COMPLETABILITY IN CLASSICAL PROBABILITY SPACES
In my talk I would like to present some results concerning the notions of „causal completeness” and „causal completability”. A probability space is causally complete if any correlation between logically independent events in it possesses an explanation by means of a common cause (in the Reichenbachian sense). The notion of causal completeness may be extended so that an explanation by other means is accepted. The first result (due to Marczyk and Wroński 2009) states that a finite probability space has a uniform probability measure iff every correlation between logically independent events in it possesses a Reichenbachian common cause or a so called Reichenbachian common cause system of size 3. The second result is that every probability space may be extended (with the measure being preserved) to a causally complete space. I also present some problems regarding extension of these results to non-classical probability spaces.
UNGROUNDED DISPOSITIONS IN QUANTUM MECHANICS
General metaphysical arguments have been proposed in favour of the thesis that all dispositions have categorical bases (Armstrong; Prior, Pargetter, Jackson). These arguments have been countered by equally general arguments in support of ungrounded dispositions (Molnar, Mumford). I believe that this controversy cannot be settled purely on the level of abstract metaphysical considerations. Instead, I propose to look for ungrounded dispositions in specific physical theories, such as quantum mechanics. I explain why non-classical properties such as spin are best interpreted as irreducible dispositional properties, and I give reasons why even seemingly classical properties, for instance position or momentum, should receive a similar treatment when interpreted in the quantum realm. Contrary to the conventional wisdom, I argue that quantum dispositions should not be limited to probabilistic dispositions (propensities), and I show reasons why even possessing well-defined values of parameters (being in an eigenstate) should qualify as dispositional properties, not categorical ones. I also discuss the issue of the actuality of quantum dispositions, arguing that it may be justified to treat them as mere potentialities whose being has a lesser degree of reality than that of classical categorical properties, due to the incompatibility relations between non-commuting observables.