A World Without Laws

Stephen MumfordUniversity of Nottingham, UK, China and Malaysia

Birmingham – Bristol – Nottingham

And God said…

Let F = GM1M2/d2,

where G = 6.67259(85) × 10-11N m2kg-2

The range of phenomena and objects in the universe is huge, from stars thirty times as massive as the Sun to microorganisms invisible to the naked eye. These objects and their interactions make up what we call the physical world. In principle, each object could behave according to its own set of laws, totally unrelated to the laws that govern all other objects. Such a universe would be chaotic and difficult to understand, but it is logically possible. That we do not live is such a chaotic universe is, to a large extent, the result of the existence of natural laws. [….] It is the role of natural laws to order and arrange things, to connect the seemingly unconnected, to provide a simple framework that ties together the universe. (Trefil 2002: xxi)

Humean Lawlessness

(Hume, Lewis)

Realism - Governing laws

(Newton, Armstrong)

Hume’s idea of causation

• Temporal priority: the cause occurs before the effect

• Contiguity: the cause and the effect are spatially adjacent

• Constant Conjunction: a type of cause is always followed by the same type of effect (causal laws are regularities)

• Necessity: when the cause occurs, the effect must occur

a cb

a cb

Dispositions/Powers

Passing powers around

Hume’s idea of causation

• Temporal priority: the cause occurs before the effect

• Contiguity: the cause and the effect are spatially adjacent

• Constant Conjunction: a type of cause is always followed by the same type of effect (causal laws are regularities)

• Necessity: when the cause occurs, the effect must occur

The powers view of causation

• Simultaneity: the cause occurs at the same time as its effect

• Contiguity: the cause and the effect are spatially adjacent, though this is an empirical truth

• Tendencies: a type of cause only tends to be followed by the same type of effect

• Dispositionality: a cause disposes towards its effect

F G

Sweet solutionSugar cube+ water

t1t2

CAUSE

EFFECT

R

F G

T

R

F G

High blood pressure

Low blood pressure

High blood pressure

Low blood pressure

Clonidine

High blood pressure

Low blood pressure

Clonidine

Beta-blocker

R

High blood pressure

Low blood pressure

Clonidine

Beta-blocker

Happiness

+

+Wealth0

t

E

C

E

C

E

C

Q1

Q2

Q3

How do we know powers?

Proprioception!

Proprioception

Physics – Biology – Social Sciences – Psychology

Getting Causes from Powers

Stephen Mumford & Rani Lill AnjumOxford University Press 2011