Observation and Theory

OHear: Chap. 5

Observational Common Ground Between Theories

Working assumption of Logical Empiricist program

Distinction between Observational and Theoretical

terms &
statements

Question: How is theory grounded in observation?

surely this is the key thing that distinguishes science

the responsiveness of its conceptions and its posits to the evidence.
the evidence of our senses: observed & experimental evidence.

and what's chiefly lacking in nonscience

groundless metaphysical speculation
pseudo-sciences like astrology

Attempts were made to define theoretical terms in terms of their observational bases

Try: X is an acid iff X turns blue litmus red, . . .
Problems with so-called operational definitions
technical difficulties

conceptual difficulty:

what it means to be an acid has more to do with theoretical interconnections

acid:

any of various typically water-soluble and sour compounds that redden litmus,
that are capable of reacting with a base to form a salt,
that are hydrogen-containing molecules or ions able to give up a proton to a base,
or that are substances able to accept an unshared pair of electrons from a base.

the true or more basic definitions 3 & 4 are entirely theoretical

if a substance meets 4 but not 1 it's still be an acid
if some substance meets 1 but not 4 it's not an acid.

Subsequent attempts tried to tie down theoretical statements to observational bases

not term by term . . . by definitions
but statement by statement: e.g. All acids give up hydrogen ions in water solutions.

confirmation and/or falsification

we make predictions from the theoretical statement: (x)(Tx -> (O1x -> O2x))
we observe O1x and O2x (or not)
if not Tx is disconfirmed
if so Tx is confirmed

assumption:

we can isolate the O statements from the Ts
and T's from each other so that
each T statement has an O basis of its own

crash & burn: the assumptions are false

we can't strictly isolate the Os and Ts.

water?
litmus?
substance?

we can't test the Ts in isolation

predictive failure always can be blamed on theory involving auxilliary hypotheses, e.g.,

from the same theoretical bailiwick: chemical theory

whether this (colorless, tasteless, odorless) liquid we poured the sample in was real water
whether this sample really dissolved

and even far afield

that our senses and instruments aren't aren't deceiving us:
optics, biology, psychology, mechanics involving auxilliary hypotheses

predictive success, likewise, accures to the whole body of statements en masse

Last gasp: Quinean attempts to tie down theories globally to observation

"The totality of our so-called knowledge or beliefs, from the most casual matters of geography and history to the profoundest laws of atomic physics or even of pure mathematics and logic, is a man-made fabric which impinges on experience only along the edges. Or, to change the figure, total science is like a field of force whose boundary conditions are experience. A conflict with experience at the periphery occasions readjustments in the interior of the field. Truth values have to be redistributed over some of our statements. Re-evaluation of some statements entails re-evaluation of others, because of their logical interconnections -- the logical laws being in turn simply certain further statements of the system, certain further elements of the field. Having re-evaluated one statement we must re-evaluate some others, whether they be statements logically connected with the first or whether they be the statements of logical connections themselves. But the total field is so undetermined by its boundary conditions, experience, that there is much latitude of choice as to what statements to re-evaluate in the light of any single contrary experience. No particular experiences are linked with any particular statements in the interior of the field, except indirectly through considerations of equilibrium affecting the field as a whole." (Two Dogmas of Empiricism, Section 6, pgph. 1)
Revised assumptions:

we can't isolate the T's from each other so that
no T statement has an O bases of its own
O-ness statements from the T-ness are distinguishable, but only by degrees

statements nearer to the experiential periphery are more observational

[2+2=4]
Acids are electron donors.
Acids are water soluble.
Water is wet.
The stuff tastes sour.

statements closer to the logical center are more theoretical: reverse the direction

O'Hear Contra Kuhn + my 2¢

Kuhnian relativism holds that paradigms are incommensurable

meaning there's no neutral rational basis for comparing theories at the highest levels
it all comes down to irrational preferences, influences, politics, and taste
i.e. "There's no objective neutral Truth

there's only paradigm relative truths

it's true for Aristotelians -- in their world or as they see it

when you're watching a "heavy body on a rope swinging back and forth on a string or chain until it comes to rest"
your seeing constrained fall

it's true for Newtonians -- in their world or as they see it

when you're watching a "heavy body on a rope swinging back and forth on a string or chain until it comes to rest"
your seeing a pendulum

But neutral description and observation is possible

examples

Kuhn's own paradigm neutral description: "heavy body on a string or chain swinging back and forth"
Gallileo's observation of moons of Jupiter

contrary to Ptolemaic expectations
Ptolemaics can still see them through their telescopes
space probes can visit them
their existence is no more paradigm specific than that of the Gallapagos Islands

discussion

granted: our observations are theory-laden in being conditioned by theoretic persuasion or paradigmatic acceptance influening

directions of interest and attention (where we look)
and even, somewhat, our perceptions themselves (what we see in looking there)
there is no presuppositionless observation (contra Bacon).

denied: our observations are paradigm-relative in being completely determined by our theoretic persuations or pardigm acceptance

devotees of different theories or paradigms
still share a deal of prescientific & extraparadigmatic common ground

presuppositons
assumptions regarding similarity and dissimilarity
interests, etc.

My 2¢

the Quinean holistic turn goes contrary to scientific relativism

no matter how basic your paradigm or theory
it will only be a piece of the continent, a part of the whole: total science
resulting commensurability

the specific disagreement between competing devotees of competing paradigms
occur against a larger background of shared agreement about much else
and their dispute can be rationally ajudicated on this basis

still open to more global cultural relativism

that global paradigms completely determine our observations
that different cultures have different global paradigms
hence scientific world-view can't be rationally vindicated against other world-views

this may be resisted along similar lines

even those with radically different global paradigms or cultures
share basic human propensities, interests, and sensory dispositions
that high-level theoretic persuations cannot override:

the native paradigm may include bullets and antibiotics in its conceptual catalog

but the natives still fall when the bullets hit them
and the antibiotics still heal their infections

may be a universal human paradigm: of object recognition, tracking abilities, etc.

so that even the most different human cultures are minor variants on underlying universal themes
so, again, against this wider, deeper shared background agreement
disputes between cultures or global paradigms can be ajudicated on this basis

Observation and Theory

Accepted wisdom

there is no pure observational level
free from any theoretical influence

Background: Logical Empiricist search for a pure observational language

phenomenalism: red patch here now, sour taste here now . . . doesn't get us far

too private & subjective:
too episodic and ineffable

physical thing language: talk of tables, chairs, ducks, people, etc.

seemed to be objectionably theory laden
carries with it all kinds of unverifiable assumptions

expectations regarding the future behavior of the things
uncheckable beliefs about their origins
hypothetical or counterfactual beliefs

about how they would behave
if circumstances were different in various ways

upshot: no pure observation basis adequate for scientific purposes can be isolated
Popper: "Here is a glass of water" v. "Here is an electron"

if we take the former as basic or observational
that's a psychological fact about us
but this preference has no basis in any difference in the character of the statements

electron & water
are thoroughly theoretical

O'Hear: Logical Empiricists needlessly rending their shirts

unable to have the whole loaf: presuppositionless -- theory pure -- observation
they won't accept half a loaf . . .
the half a loaf

some statements are more observational: there's a smoky trail in the cloud chamber
than others: that's an electron trail passing through the cloud chamber

water v. electrons

the belief that a certain liquid is water
may bring with it expectations about it's future, past, and counterfactual dispositions

that it will quench thirst
that it will drown us if we try to breath it
that it will boil if we put it in the teapot and the teapot on the stove

which are not at all the same as holding any explicit theory about water

upshot contra Kuhn

interacting with things like glasses of water being what we're all humans are programmed by evolution
we don't just arbitrarily `decide' to take this level as basic or observational
this basic level of observation -- our "lived world"

being "related

to our genetic inheritance
and our needs and interests as human beings

provides

a common ground for communication -- and mutual criticism and comparison of beliefs -- between people of different cultures
a fortiori across paradigms

between Western (influenced) scientists)
pursuing basically the same enterprise

Empiricism

"Observational" basis is there in the life-world conceptions & beliefs all people more or less share

given the similarity of our biology & sense organs
and the similar behavioral dillemas all people & societies face regarding

food & shelter
fight & flight
fraternization

Empiricism -- the view that knowledge is anchored in sensory interactions with the world -- is vindicated along these lines

at the life-world level "changes in the world are most readily registered as changes in our sensory experience"
theory has to answer to these pre-theoretical everyday observations and experiences (96).

Remaining difficulty

Much of our scientific knowledge is not about unobservable objects and processes far removed from the life-world

electrons, mesons, quarks, charm, spin,
the Big Bang,
etc.

The difficulty: what's the relation

between observable phenomena
and the unobservable things that scientific theories describe

Unobservability and Underdetermination

Unobservables

things known only through their effects or theoretically posited to explain certain effects
cells, molecules, atoms, electrons, mesons, quarks? (query class: wut is there?)

a sliding scale depending on observational instruments & opportunity

where's the line now?
how low can you go?

the lower
the more dependent on technological assistance
thereby assuming all the theory behind it

conclusion

instrument assistance yeilds diminishing returns
observability diminishes to near zero for quarks & their ilk

Underdetermination of theories by observational data

data is like points on a graph
any number of lines can go through all the points

both the grue hypothesis and the green hypothesis agree with all the data
always be indefinitely many alternative theories

invoking radically different concepts & positing different sorts of entities
or rearranging ideas about familiar concepts & entities (if this is conceivable)

simplicity rears it's beautiful head again:

What is simplicity? (isn't it in the eye of the beholder)
What warrant is there for thinking the "simplest" curve most probable?

Gripes about Gravity

a suspect notion from the beginning

acted instantaneously at a distance
contrary to 1st methodological principle of mechanism: No action at a distance.

compare astrology
compare Aristotelean elements seeking their natural place

Newton himself resisted it & regarded it as a bit of an embarassment
Kuhn tamed

the importance of the methodological constraint of mechanism lends credence

to Kuhns description of paradigms as encompassing standards
and his revolutionary portrayal of the shift

the shift from Aristotelian/Scholastic paradigm
to Mechanistic/Newtonian paradigm

incommensurability undermined

paradigms can fall short by their own internal standards
gravity was scandalous y the mechanistic philosophy's own lights

Einsteinian revolution (the new paradigm) better by the old paradigms lights!

gravitation explained by the curvature of space around material bodies
not by any special force

Berkeley's issue

"As far as [gravitational] attraction is concerned it is clear it was not introduced by Newton as a true physical quality but merely as a mathematical hypothesis." (De Motu sec. 17 as cited by O'Hear, p. 102)

gravity, according to Berkeley, is a counter introduced to enable mathematically precise predictions of observed events
but has no real reference to anything in the world

there's this formula that predicts stuff F = [(M1*M2 / d²) * g]
no force of gravitational attraction to which this formula refers

Newton's distinction

phenomenological laws: correlations among observable phenomena
hypotheses: about unobservable underlying causes

If gravity interpereted as a mere phenomenological law

the claim "that gravity does really exists and acts according to the laws we have explained" (Newton as cited by O'Hear, p. 104)
amounts to no more than "the observation that certain regularities in accordance with the inverse square law obtain" ( p. 104)

Berkeley's misgivings vindicated by Einsteinian reconstrual of "gravitational attraction"

as curvature of space
Newton's law of universal gravitation still obstains: still predicts the phenomena
but there really is no force answering to the name of "gravity" answering to

Undertermination illustrated by the predictive agreement between

the Newtonian occult force account
and the Einsteinian curved space account

Final Issues

gravitrons?
uncommon "observables"

electricity (electrons?) when you stick your finger in the outlet?
gravity every waking moment you're on earth?