The reductionist blind spot:

1
The reductionist blind spot
higher-level entities and the laws they obey

• Russ Abbott
• Department of Computer Science
• California State University, Los Angeles

2
Starting with the basic laws of physics it
ought to be possible to arrive at the theory
of every natural process, including life, by
means of pure deduction.
Starting with the basic laws of physics it
ought to be possible to arrive at the theory
of every natural process, including life, by
means of pure deduction. Einstein
All of nature is the way it is because of
simple universal laws, to which all other
scientific laws may in some sense be reduced.
There are no principles of chemistry that simply
stand on their own, without needing to be
explained reductively from the properties of
electrons and atomic nuclei, and there are no
principles of psychology that are free-standing.
All of nature is the way it is because of
simple universal laws, to which all other
scientific laws may in some sense be reduced.
There are no principles of chemistry that simply
stand on their own, without needing to be
explained reductively from the properties of
electrons and atomic nuclei, and there are no
principles of psychology that are free-standing.
Weinberg

• Living matter, while not eluding the laws of
  physics is likely to involve other laws,
  which will form just as integral a part of
  its science.

Living matter, while not eluding the laws of
physics is likely to involve other laws,
which will form just as integral a part of
its science. Schrödinger
The ability to reduce everything to simple
fundamental laws does not imply the ability to
start from those laws and reconstruct the
universe.
The ability to reduce everything to simple
fundamental laws does not imply the ability to
start from those laws and reconstruct the
universe. Anderson
3
The reductionist challenge
Well, I admit that I dont know why. I dont even
know how to think about why. I expect to figure
out why there is anything except physics the day
before I figure out why there is anything at all.
Why is there anything except physics?
Why is there anything except physics? Fodor,
1998

• If a higher level explanation can be related to
  physical processes, it becomes redundant since
  the explanatory work can be done by physics.
• Maurice Schouten and Huib Looren de Jong, The
  Matter of the Mind, 2007

The point of this talk is to show why the higher
level isnt redundant and why there is something
besides physics.
4
Emergence
Emergence, 2008
Paul Humphreys
Mark Bedau

• Phenomena that arise from and depend on some more
  basic phenomena yet are simultaneously autonomous
  from that base.
• The very idea of emergence seems opaque, and
  perhaps even incoherent.
• When we finally understand what emergence truly
  is we will know whether there are any genuine
  examples of emergence.
• How should emergence be defined?
  irreducibility, unpredictability, conceptual
  novelty, ontological novelty, supervenience?
• In what ways are emergent phenomena autonomous
  from their emergent bases? irreducible to their
  bases, inexplicable from them, unpredictable from
  them, supervenient on them, multiply realizable
  in them?
• Does emergence necessarily involve novel causal
  powers, especially powers that produce downward
  causation?
• Emergence is simultaneously palpable and
  confusing.

Backup slide
5
Its not all that mysterious
Backup slide

• Do higher-level entities exist?
• Game of Life Turing Machines and biological
  entities.
• Do higher-level entities obey autonomous higher
  level laws?
• Turing machines are subject to the theory of
  computability, which is independent of the rules
  of the Game of Life.
• Biological entities are subject to evolution
  through natural selection, which is defined
  independently of the underlying physics.
• Is this surprising?
• Higher level entities are built by imposing
  constraints on lower level elements. A
  constrained system implements additional
  laws/mechanisms.
• Is this trivial?
• Higher level entities and laws/mechanisms are
  causally reducible but ontologically real,
  resolving the reductionist challenge.
• Reducing away higher level entities and the
  laws/mechanisms they implement creates a
  reductionist blind spot and is bad science.
• Corollary the principle of ontological emergence.

• Do higher-level entities exist? Yes. Higher level
  entities are real.
• Game of Life Turing Machines and biological
  entities.
• Do higher-level entities obey autonomous higher
  level laws? Yes.
• Turing machines are subject to the theory of
  computability, which is independent of the rules
  of the Game of Life.
• Biological entities are subject to evolution
  through natural selection, which is defined
  independently of the underlying physics.
• Is this surprising? No.
• Higher level entities are built by imposing
  constraints on lower level elements. A
  constrained system implements additional
  laws/mechanisms.
• Is this trivial? Yes, but it has significant
  implications.
• Higher level entities and laws/mechanisms are
  causally reducible but ontologically real,
  resolving the reductionist challenge.
• Reducing away higher level entities and the
  laws/mechanisms they implement creates a
  reductionist blind spot and is bad science.
• Corollary the principle of ontological emergence.

6
Turing machines and the Game of Life
http//www.ibiblio.org/lifepatterns/
Nothing really moves. Just cells going on and off.
The glider pattern
By suitably arranging Game of Life patterns, one
can simulate a Turing machine. ?The GoL can
compute any computable function. Its halting
problem is undecidable.
7
A GoL Turing machine

• is an entity.
• Like a glider, it is recognizable it has reduced
  entropy it persists and has coherenceeven
  though it is nothing but patterns created by
  cells going on and off.
• obeys laws from the theory of computability.

Reductionism holds. Everything that happens on a
GoL grid is a result of the application of the
GoL rules and nothing else.
Computability theory is independent of the GoL
rules.

• is a GoL phenomenon that obeys laws that are
  independent of the GoL rules while at the same
  time being completely determined by the GoL rules.

Just as Schrödinger said.
8
Downward causation?

Downward causation entailment

• Is it strange that the unsolvability of the TM
  halting problem entails the unsolvability of the
  GoL halting problem?
• We import a new and independent theory into the
  GoL and use it to draw conclusions about the GoL.

This is called reduction in Computer Science.
We reduce the question of GoL unsolvability to
the question of TM unsolvability by constructing
a TM within a GoL universe.
9
Not surprisingA constrained system is likely to
obey special rules
1. Spoon the water into an ice cube tray.
2. Freeze the water, thereby constraining its
molecules into a rigid lattice structure.
3. Remove the frozen water from the tray.
4. Hurl the water stone at the window.
10
(No Transcript)
11
Not surprisingA constrained system is likely to
obey special rules
Frozen water implements a solid. It can be used
like a solid, and it obeys the laws of solids.
(Thats because it is a solidwhich is an
abstraction.) Is this a trivial observation? Is
it just common sense?
1. Spoon the water into an ice cube tray.
2. Freeze the water, thereby constraining its
molecules into a rigid lattice structure.
3. Remove the frozen water from the tray.
So if we constrain the GoL to act like a TM, it
shouldnt be surprising that it is governed by TM
laws.
4. Hurl the water stone at the window.
A phase transition often signals the imposition
or removal of a constraint.
12
Causally reducible ontologically real

• GoL Turing machines are causally reducible but
  ontologically real.
• You can reduce them away without changing how a
  GoL run will proceed.
• Yet they exist as higher level entities and obey
  laws not derivable from the GoL rules.
• They come into being as a result of constraints
  imposed on an underlying system.

Reducing everything to the level of the GoL rules
results in a blind spot regarding higher level
entities and the laws/mechanisms that govern them.

• This is the essence of software. Software
  constrains a computer to behave like something
  elsesuch as a slide projector.
• All executing software applications are causally
  reducible yet ontologically real.

13
Evolution is to Physics as Computability is to
the Game of Life

• Namely, autonomous.
• Evolution is about
• populations of abstract entities
• the mutation and combination of abstract
  properties that make those abstract entities more
  or less suited to their abstract environment
• the influence of that suitability on the ability
  of those abstract entities to survive and
  reproducethereby generating more abstract
  entities.
• Evolution is an abstract process that operates on
  abstract entities.
• E.g., evolutionary computing generates solutions
  to difficult optimization and design problems.

• Biology is physical.
• Lets stipulate that its possible to reduce
  biology to physics
• that nature builds biological entities from
  elementary particles
• that its (theoretically) possible to trace how
  any state of the worldincluding the biological
  organisms in itcame about by tracking elementary
  particle wave functionsalong with quantum
  randomness.
• This parallels the fact that its possible to
  trace the operation of a GoL Turing machine by
  tracking GoL cell transitions.

14
Recognize biological entities as real and apply
the abstraction of evolution to them.
Deny the reality of biological entities. Reduce
biology to physics.
Biologys options
In doing so, Darwin and Wallace implicitly
predicted that biological entities must have a
way of transmitting information about properties.
DNA proved them right.
Throw away evolution and biological entities
and hence biology creating another reductionist
blind spot.
This is simply bad science.
15
Level of abstraction
Two backup slides

• A collection of entities and relationships that
  can be described independently of their
  implementation.
• A Turing machine biological entities every
  computer application, e.g., PowerPoint.

• When implemented, a level of abstraction is
  causally reducible to its implementation.
• You can look at the implementation to see how it
  works.

• Its independent description makes it
  ontologically real.
• How it behaves depends on its description at its
  level of abstraction, which is independent of its
  implementation.
• The description cant be reduced away to the
  implementation without losing information.
• If the level of abstraction is about nature,
  reducing it away is bad science.

16
Does nature uselevels of abstraction?

• Given the imposition of some (random)
  constraints, what entities result? Two
  possibilities.
• There are none, or they dont persist. Back to
  natures drawing board.
• They persist and by their interaction create a
  new level of abstraction.
• Nature then asks what can I build on top of
  that? (Think James Burkes Connections.)
• Software developers do the same thing.
• Its all very bottom-upand in natures case
  random. Each new entity or level of abstraction
  creates a range of possible laws/mechanisms that
  didnt exist before.
• These could not have been deduced from lower
  levelsexcept through exhaustive enumeration.

17
The principle ofontological emergence

• Extant entities and levels of abstraction are
  those whose implementations have materialized and
  whose environments enable their persistence.

18
Is that it?
Does this resolve the problem of reductionism vs.
the special sciences?
Does it explain emergence?
Is it too easy?
19
Three kinds of material entities
Real objectively observable
All have reduced entropy persistent patterns.

• Static atoms, molecules, solar systems, most
  engineered artifacts.
• Persist within energy wells. Energy is required
  to destroy them.
• Supervenience works well.
• Less mass than the aggregate of their components.
• Dynamic biological and social entities,
  hurricanes.
• Extract energy from the environment to persist.
  May be destroyed by cutting off energy supply.
• Since dynamic entities supervene over constantly
  changing collections of lower level elements,
  supervenience doesnt work well.
• The atoms and molecules making up our bodies
  change daily.
• The members of most social units (a country, a
  corporation, a club, etc.) change.
• More mass than the aggregate of their components.
• Symbolic software entities.
• Persist within a symbolic support framework
  computers. May be destroyed by destroying the
  framework. No individual energy issue.
• Since symbolic entities supervene over
  (potentially unbounded numbers) of bits,
  supervenience doesnt work well. Debugging can be
  hard.
• No mass issue.

Distinctive mass properties.
20
Levels of abstraction

• Used by scientists to characterize how some
  aspect of nature, i.e., some groups of entities,
  operates.
• How can I describe the level of abstraction that
  nature is implementinge.g., evolution in
  biology?
• Used by mathematicians as axioms for a
  mathematical subfielde.g., Peanos axioms for
  the natural numbers.
• What are the logical consequences of this level
  of abstraction?
• Used by computer scientists to create new
  applications.
• This level of abstraction characterizes the
  entities and operations that we want the software
  to implement.
• This level of abstraction is cool.

21
Abstract data types levels of abstraction

• A collection of types (categories/kinds),
  operations that may be applied to entities of
  those types, and often constraints that are
  required to hold.
• Simple examples stack, naturals.

• Every computer program, e.g., PowerPoint,
  implements a level of abstractiontypically
  including a number of abstract data types.
• The things you can manipulate.
• What you can (and cant) do with them.

22
Whats different?

• This is an bottom-up, platform-based, creativity,
  and implementation based view rather than a
  top-down analysis view.
• Yes, there is multiple realization, but what
  matters is what functionality gets created, not
  whether there are multiple ways to realize it.
• The eye may or may not have evolved multiple
  times. What matters is that it added (some sort
  of) vision each time it did.
• Software developers (and engineers and
  practitioners in any other creative discipline)
  ask
• How can I create something new, e.g., a new level
  of abstraction a novel, a painting, a sculpture
  by molding/shaping what currently exists?
• The higher level is no more deduced from the
  substrate than a painting, a novel, or a
  sculpture is deduced from the palette, set or
  words, or clay.
• Once done, we ask what I can build using this as
  a building block?
• In nature, there is no advance specificationother
  than the implicit specification implied by the
  environment. Once created, each new entity class
  adds new abstraction possibilities.