Manifestation of powers:
timing and continuity
John Pemberton
21 November 2012
Manifestation of physical powers
• Credible account of powers ↔ clear account of timing of manifestations of powers
Change
Compresence
Mutual
manifestation
partner 1
Property 1
Property 2
Resultant set of
properties
Set of mutual
manifestation
partners
Property a
Property b
…
…
• Ambiguity concerning manifestation – is it:
1. End state – i.e. a new set of properties (relational / causal profile account of powers)
2. A process of change (which brings about an end state featuring resultant set of
properties)
• Aristotle careful to make such distinctions concerning change
• Nowadays less careful – e.g. use of term “event”
• Let’s look at options for how change / timing might work
Option 1: Manifestation is (1) new
state and (2) is not time extended
• Now future history is some stepwise manifestations of
powers
– If finite number of powers in Universe:
• Future history is not time extended
• Even if countably infinite sequence of future
manifestations (still has measure zero)
– Perhaps Universe contains infinite number of powers
and uncountably many future manifestations
• Does not seem consistent with examples, e.g. fragility,
solubility, power to heat
Option 2: Manifestation is (1) new
state and (2) is time extended
•
•
What happens in between start and end? Can’t leave ontological gap
Perhaps there are intermediate steps:
Mutual
manifestation
partner 1
Manifestation
1
Manifestation
2
…
Manifestation
Property 1
Property 2
.
.
•
•
•
•
If temporal gaps between states, then same problem 1 level down
– Need red arrows to have zero time extension
Perhaps compresence is time extended event – and (in limit) events are contiguous
Face Russell-type challenge:
– Static time-extended events problematic – why does change occur now?
– If exercising of power is not at end of change-event, then still lack contiguity
– Power driven change at arrows – with other change during events?
Original power is e.g. not power of glass to smash – but power of glass to become
stressed
Option 3: Manifestation is continuous
process of change (resulting in new state)
Mutual
manifestation
partner 1
Property 1
Property 2
Manifestation
outcome
Continuous path through
property state space
Property a
Property b
Property c
…
.
.
• But – need clarification:
– Are all properties determinable? If not: what does continuity of
property amount to?
– May end with different number of things and properties
– E.g. how can single, smooth, round object (e.g. glass) go through such
continuous property change to produce lots of sharp, differentlyshaped fragments
• Need account of what continuity of change amounts to
Option 3 contd.
• Power of original object sets trajectory through
property state space, it seems
– But how?
– By assumption it is not stepwise process
– Does control reach across time to guide through to end
point?
• Suppose just after glass hits ground and start to smash
a strong wind suddenly starts
– I suppose that how glass flies off is changed by wind
– If so, manifestation of power is not “pre-programmed”
absolutely – but only its “direction” is set (through to the
end)
What can we learn from the practice
of science?
• How does (everyday) science model manifestations of physical
powers?
• Look at some typical examples
• Scientific practice suggests that powers exhibit differing
characteristics as to the timing and form of their manifestations
• Draw rough characterisation of 2 types of manifestation which
seem distinct:
1. Force-manifestations
2. Rearrangement-manifestations
•
Note some (prima facie) others types of manifestations
Force manifestations - examples
• Pulling of object, e.g.:
– Rope
– Spring
– Lifting rod
• Pushing of object
– Lever
– Cog (on interlocking cog)
– Gas pressure
• Gravitational attraction
• Electromagnetic attraction / repulsion
Two horses pulling a barge
Horse 1
Horse 2
•
•
•
•
•
•
•
See e.g. J. S. Mill, Cartwright, Molnar
Horses have the power to pull on rope
Manifestation of the pulling is a contribution
In this case contribution is a force
– Force from horse 1: NE
– Force from horse 2: SE
Manifestations is not a movement:
– Barge is pulled E - the barge does not move NE or SE
(Manifestation = exercising)
Movement arises from combination of forces in the given arrangement
Force-manifestations
•
•
•
•
•
•
•
Manifestation is a force
Force is a contribution to change
Given suitable machine arrangement (e.g. rigid bodies) forces combine by vector
addition
– Doesn’t seem to depend on what produces the force (e.g. gravity,
electromagnetism, pulling from rope, gas pressure)
– Manifesting is immediate and homogeneous – a directed pulling (or pushing)
• Direction and strength can change continuously through time
Force must be time-extended
– Science does not feature forces which exist for a single point in time
– Eleatic Stranger’s principle for existence
– (Force exists at each point in time during relevant time-period)
Force-powers are correlative
Power continues to exist throughout manifesting
Relativistic or QM modifications sometimes required to Newtonian story – here
focus on mid-size slowish domain where accounts must agree closely
Rearrangement-manifestations
• Manifestations which include movement of things from
one place to another
– And thus typically acceleration of things, changes in
velocities, changes in orientation (i.e. rotation)
• Rearrangement manifestations:
– Take time (movement from one place to another is
not instantaneous)
– Non-homogeneous stages
• Changes in other properties of things also typically occur
during rearrangement manifestation, perhaps e.g.:
– temperature, wear-and-tear, colour, etc.
Pendulum: power to oscillate / swing
Startarrangement
•
•
•
•
•
Endarrangement
Manifestation:
– Bob exercises power to attract / be attracted by the Earth;
– String exercises power to pull bob towards the pivot
– Bob moves around arc
Forces combine in this arrangement to produce the swing of the bob
– Which is the manifestation of the pendulum’s power to swing in this case
Arrangement matters: Parts must be positioned and connected in the right way,
e.g. string must be tied to bob and other end to the pivot
Parts have distinct properties: bob is dense mass; string is sufficiently strong; pivot
is fixed
Example typical of many other rigid body dynamic cases
Rearrangement manifestation involving
movement of fluid: cistern flush
•
Cistern has power to flush
When the handle is turned, the lever (which has
the power to pull up the lift rod) pulls up the lift
rod (which has the power to open the outlet
valve) which opens the outlet valve (which has
the power to release water from the cistern),
which releases water from the cistern, which
lowers the ball-cock, which opens the inlet
valve,…
•
•
•
Manifestation involves nicely sequenced
exercising of powers of parts
Powers of each component combine together in
the machine arrangement to produce a
manifestation of the power to flush
– i.e. release of flush and refill of cistern
Manifestation of power is a rearrangement
which involves movement of fluid
Chemical rearrangement: hydrogen-oxygen
explosion
O
H
Startarrangement
•
•
•
•
H
O
H
O
H
H
H
O
H
H
Endarrangement
Hydrogen gas has power to explode (with oxygen) to produce water
Manifestation:
– H² and O² have power to separate in to atoms when sparked
– The hydrogen and oxygen atoms have power to bond as H²O, and give out
energy (which may separate more H² and O²)
– Change process is explosion
Manifestation is a rearrangement:
– Occurs quickly – but not instantaneously
– Involves breaking and forming of (atomic) bonds
– Involves subatomic forces / energy release
Other examples: solubility
Example: synaptic transmission
Smashing of glass
• Manifestation is rearrangement
• Involves breaking of microstructural (chemical)
bonds
• One thing → many things
Rearrangement manifestations
• Time extended
• Arrangement (structure) of things is central:
– It fixes locations of powers – and thus what they do in this context
– It is what changes when things move from one place to another
• Thing with rearrangement power may or may not survive manifestation
• A story we can sometimes tell about rearrangement manifestation is
(roughly):
– Structure coordinates forces to produce rearrangement
• This story is incomplete, e.g.:
– Fluid flow
– Chemical rearrangement
– Breaking and forming of bindings
– Strong and weak forces
– Relativistic / QM considerations
• …but it does seem to be an important part of the story
• To the extent we can tell this story, we have a nice account of how
continuous process manifestations come about
Smashing glass + wind
• Structure-coordinating-forces story also
provides nice account of this case
• Wind is an additional force which starts to
operate during the unfolding rearrangement
• Forces combine in the given arrangement at
each stage:
– Forces in glass (and pieces of glass) from smashing
– Forces due to wind
Some other types of powers
• Generic powers
– E.g. to walk, fly, bark, solubility, fragility, etc.
– Can these be equated with rearrangement
powers?
• Change to properties (other than structure)
– E.g. (perhaps) power to make red
• Animal powers
• Human powers
• Power of God
Metaphysics of power manifestations
• What implications, if any, do these scientific
considerations have for metaphysical account
of power manifestations?
• Metaphysics should be adequate basis for
basic science
• Let’s suppose that the world includes forcepowers and rearrangement-powers (roughly
as characterised) – what then?
Metaphysical implications
•
•
•
•
Force-powers:
– When forces give rise to change, this change involves acceleration and
movement which is continuous through time
– Consistent with powers giving rise to continuous processes of change
– Power persists through manifestation
Rearrangement-powers:
– Involve movement from one place to another
• Difficult to regard this movement of a thing as a property (E J Lowe)
• (Velocity may be property)
– This movement is continuous process
Favours view that: manifestations are processes not state-changes
But perhaps others might argue:
1. No force-powers and/or rearrangement-powers (in ontology)
2. Science is deceived – force & rearrangement manifestations are statechanges
3. Only some manifestations are processes
4. Other
Favours view that arrangement /
structure matters
•
•
•
•
Position of powers affects:
1. how they manifest
2. how manifestations combine
Change in the arrangement is often a central part of the manifestation
– i.e. move of part from one place (or orientation) to another
The structure-composes-force story:
– Scientifically compelling
– Suggests way we might integrate the metaphysical accounts of force-powers
and rearrangement-powers - appeals to parsimony
– Offers (remarkably nice) solution to the problem of manifestation timing
•
Interplay of force-manifestations, accelerations, velocities, ∆position
through time, arrangement
•
Perhaps familiarity with Newtonian mechanics makes us overlook
•
Seems to be the only solution currently on the table
We need robust account of structure
Need for robust structure
Prop 1
Prop 2
…
Property 1
Property 2
…
Property 1
Property 2
…
•
Seem to need structure which allows for:
– Separate (potential) parts
– Each part has its own:
• Position
• Properties / powers
– Bindings link specific parts
List of properties does not seem
adequate
Property 1
Property 2
…
Position prpty 1
Position prpty 2
…
Binding type 1
…
•
•
•
Prop 1
Prop 2
…
Property 1
Property 2
…
Property 1
Property 2
…
Need position properties to be associated with subset of properties / powers of
list
Bindings
– Link specific parts: need to be cross-referenced to these parts
– Not just another compresent entity
Not clear that we can derive arrangement/structure of parts from property lists
– So that e.g. butane and iso-butane are distinct
Molnar
• Molnar argues that positions are non-powers
– What is the manifestation of a position?
– Positions central to how powers operate
– Position of powers matter - not just another
item on the property/power list
– Points towards need for structure
Aristotle
•
•
Powers in modern science are Aristotelian:
– Cartwright & Pemberton
– Correlative, persist through change, arrangement matters, give rise to
continuous change
Provisional view: things in modern science are Aristotelian
– Changing material
– Substantial forms are more than list of properties
•
Seems to include (some sort of) structure
– Restricted mereology
•
heaps, bundles, artefacts, substances
– Admits bindings: heap → bundle
•
Tyings, boltings, nailings, gluings, hookings, shape interlockings, chemical
bondings, etc.
•
Arise from (juxtapositional) arrangement of things
– In science bindings are often a mereological principle
– Questions:
•
Can Aristotelian bindings do: parts → artefact?
•
Does Aristotle allow that artefacts have substantial (or other) forms
Summary
• Manifestation timing and continuity:
– How is this supposed to work?
• Modern science suggests:
– (Many) manifestations are continuous
processes
– Structure is often central to the manifestation
• For a metaphysics in which powers give rise to
processes of change, we seem to need structure
• What is account of powers without structure?
• Aristotle’s things and powers seem promising
basis for modern science