1. Lecture 12: Metaphysics and science
Dr. Donnchadh O’Conaill
2/3/2017
Metaphysics University of Helsinki

2. 1. Introduction
Metaphysics as studying the structure of reality: ontological categories, relations between entities, which entities and categories are fundamental, etc.
General question: how does this discipline relate to other ways of investigating the world, e.g., the sciences?
More specific questions: will arise given certain answers to the general question – e.g.
Metaphysics as the primary way of understanding reality
Natural sciences as the primary ways

3. 2. Metaphysics as first philosophy
First philosophy: basis for all other investigations of reality
Metaphysics as first philosophy:
Studies what is most fundamental and general
Lays down conditions for more specific investigations: whatever else is true of their subject matter, it must conform to a true first philosophy
This view of metaphysics was dominant among the rationalists, but is now much less popular
Due in part to the failure of metaphysics to provide a single, generally acceptable worldview

4. 3. Scepticism about traditional metaphysics
Scepticism about traditional metaphysics has a variety of sources:
Empiricism, Kantianism (see lecture 1)
Another source: naturalism or scientism – the (natural) sciences are the best way of investigating reality
“deep metaphysics is too far removed from the details of scientific investigation to yield anything worth having at all” Chakravartty, 29
Traditional metaphysics places “great emphasis on preserving common sense and intuitions” Ross et al, 12

5. But metaphysician’s intuitions often not commonsensical
And neither intuitions nor common sense are reliable guides to reality: “science, especially physica, has shown us that the universe is very strange to our inherited conception of what it is like” Ross et al, 10
“Philosophers have often regarded as impossible states of affairs that science has some to entertain” Ross et al, 16 – e.g., Henri Bergson’s criticisms of relativity
Metaphysics has failed to develop an accepted body of truths or a method which all metaphysicians share
One solution: metaphysics must be naturalised

6. 4. Naturalised metaphysics
What distinguishes naturalised from traditional metaphysics?
Not subject matter, or aims, but methods
“It is the idea of a priori stipulation and theorizing with no significant empirical tethering that generates worries about some approaches to metaphysics relative to others” Chakravartty, 32
“Naturalized metaphysics is metaphysics that is inspired by and constrained by the output of our best science” Chakravartty 33
(1) how to understand this constraint?
(2) constrained by what?

7. Constrained by what?
Describing metaphysics as a priori suggests that what is required is a posteriori, i.e., empirical, constraint
But not all scientific theorising is empirical: different ways in which theories can be related to empirical findings
String theory: no (currently) testable predications
Proponents of string theory believe “it must contain a grain of truth even though it relies on extra dimensions that we can never observe” Ellis & Silk, 321
“what potential observational or experimental evidence is there that would persuade you that the theory is wrong and lead you to abandoning it? If there is none, it is not a scientific theory” Ellis & Silk, 323

8. Similar questions concerning certain interpretations of quantum mechanics (e.g., many-worlds interpretation)
Natural selection: can it be falsified empirically?
Furthermore, “the very possibility of framing and subsequently probing a hypothesis, empirically, requires that scientists presuppose an ontological scheme of possibilities within which the hypothesis can be formulated” Chakravartty 35
This ‘ontological scheme’ can be understood in different ways (e.g., realist, Kantian, etc.) but it will at least include certain a priori elements

9. 5. What kind of constraint?
Metaphysics should be continuous with science: “it must stand in a certain kind of sanctioning relation to empirical inquiry” Chakravartty 41
What is this continuity? Consistency is too weak: most metaphysical theories are consistent with empirical findings (hence the impossibility of testing them)
Nor can it be entailment: generally recognised that scientific theories underdetermine metaphysics, i.e., any scientific theory is compatible with many metaphysical positions and so entails none of them

10. Chakravartty suggests two criteria:
(a) Experiential distance: “the distance of the object of inquiry from perception by the unaided senses” 45
E.g., can the object be directly experienced and detected perceptually, or must we infer it theoretically?
Spectrum of cases, from directly perceivable to completely theoretical
Not enough that the object be perceived, but it must be detectable, i.e., can one distinguish it based on perception alone?

11. (b) Risk: “how susceptible a hypotheses or a theory is to disconfirmation in light of the results of empirical work” Chakravartty 45
The greater the degree of risk, the closer a theory is to empirical results, and the more continuity it shares with the sciences
Traditional metaphysics seems to fare badly on both risk and experiential distance
How many of the theories we have considered were susceptible to empirical disconfirmation?

12. 6. Metaphysics as a toolbox
Another way of thinking of the relation between metaphysics and science: “the products of analytic metaphysics can be regarded as available for plundering by philosophers of science” French & McKenzie, 44
Philosophers of science, in developing philosophical interpretations of scientific findings and theories, can use the resources of metaphysics, e.g., categories
Similar to the way mathematical physics draws on work from pure mathematics

13. Works cited
George Ellis & Joe Silk (2014) ‘Defend the Integrity of Physics’ Nature 515:
Steven French & Kerry McKenzie (2012) ‘Thinking Outside the Toolbox’ European Journal of Analytic Philosophy 8 (1):
Don Ross, James Ladyman & David Spurrett (2007) ‘In Defence of Scientism’, in James Ladyman & Don Ross Every Thing Must Go: Metaphysics Naturalized. Oxford: Oxford University Press.