Topics in Philosophy of Science Week 2: Laws of Nature Niels - - PowerPoint PPT Presentation

Topics in Philosophy of Science Week 2: Laws of Nature

Niels Martens

Slides, reading list & handout available at http://users.ox.ac.uk/~corp2044

2 May 2016

Today: Laws of Nature

1

Why care?

2

Regularity approach vs. governing laws

3

Criticisms

4

Discussion

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Desiderata

Universality Problem of Induction Law-like vs. accidental regularities

All gold spheres are less than a mile in diameter All uranium spheres are less than a mile in diameter

(Im)possibility & Counterfactuals: modality Explanation Prediction Understanding nature

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Regularities vs. Governing law

Governing law: laws make things happen Regularity approach: things just are, and laws are specific paterns exhibited by those maters of fact A metaphysical debate, not an epistemological one

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Regularities vs. Governing law

Motivations

Governing Laws:

Primitive Modality Realism Scientific practice Folk practice

Regularities:

Empiricism/ anti-realism Ontological parsimony Against necessary connections

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Governing Laws

1

Dispositionalism (Bird, 2005)

Primitive modal properties of particles that fix their behaviour Local

2

Primitivism (Maudlin, 2007)

Fundamental Laws of Temporal Evolution Global

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Laws as regularities

Humean Supervenience

“

laws are parasitic on occurent facts

Earman, 1984”

“

Humean supervenience is named in honor of the greater [sic] denier of nec- essary connections. It is the doctrine that all there is to the world is a vast mosaic of local maters of fact, just one litle thing and then another. ... We have geometry: a system of external relations of spatio-temporal dis- tances between points. Maybe points of spacetime itself, maybe pointsized bits of mater or aether fields, maybe both. And at those points we have local qualities: perfectly natural instrinsic properties which require noth- ing bigger than a point at which to be instantiated. For short: we have an arrangement of qualities. And that is all. All else supervenes on that.

Lewis, 1986”

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Laws as regularities

Mill-Ramsey-Lewis Best Systems Account

Popular way of cashing out the exact way in which the laws supervene on the mosaic Laws are theorems of the ‘best’ axiomatisations of the Humean mosaic best = ‘simplest’ + ‘strongest’

(Lewis, 1973; Earman, 1984)

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Two-minute Break

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Criticising Humean Laws

1

Laws only given “at end of time”

2

What is ‘best’?

3

Including non-laws as laws

4

Probabilities

5

How do we get possibilities? Counterfactuals?

6

Ontological parsimony, really?

7

Against common sense

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Criticising Humean Laws

...continued

8

Non-supervenience objection (Tooley, 1977; Maudlin, 2007)

9

Non-fundamentality objection (Maudlin, 2007)

“

[N]othing in scientific practice suggests that one ought to try to re- duce fundamental laws to anything else. Physicists simply postulate fundamental laws, then try to figure out how to test their theories; they nowhere even atempt to analyze those laws in terms of pat- terns of instantiation of physical quantities. The practice of science, I suggest, takes fundamental laws of nature as further unanalyzable

• primitives. As philosophers, I think we can do no beter than to follow

this lead.

Maudlin, 2007, p.105”

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Criticising Humean Laws

...continued

8

Non-supervenience objection (Tooley, 1977; Maudlin, 2007)

9

Non-fundamentality objection (Maudlin, 2007)

10 Explanatory Circularity 11 Non-seperability Niels Martens Topics in PhilSci - Laws of Nature 11/14

Criticising Governing Laws

1

Problem of Induction

2

New Riddle of Induction

3

Generic anti-realist/ empiricist considerations

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Governing Laws: in-house debate

Against primitivism

Uninstantiated laws Where do the laws live?

Qantum non-locality blurrs the distinction between primitivism and dispositionalism

(Dorato & Esfeld, forthcoming)

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Qestions?

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