Philosophy of
Science: Logical Positivism
Professor
Jeffery Kasser produced a series of 36 lectures through The Great Courses entitled Philosophy
of Science.
These
are my notes, commentary, and synopsis from Kasser’s lectures. The author of this blog highly recommends
this course as a high quality lecture on the philosophy of science.
One may
purchase the entire course here.
Introductory Note
The efforts, struggles, and spectacular failures of Logical
Positivism illustrate that the problems philosophy reveals about certain ideas
eventually return to haunt us.
Connecting ideas to experience to find Truth is extremely
difficult. This discussion reveals the
stubbornness of the problem, and perhaps the equal - or greater - stubbornness
of Positivists.
Synopsis
Logical Positivists influenced the Philosophy of Science for
several decades. They also made the
Philosophy of Science a major study. As
was the case with the Classical Empiricists, Einstein and others’ work in
Physics impressed them. 19th
and late 20th century German philosophy was the main impetus driving
them; they did not like the direction German philosophers were taking
philosophy. Positivists believed that
the philosophy of the day was speculative and an obstacle to scientific
progress. They were not worried about
Pseudoscience as was Popper. They
worried that metaphysics and philosophy were getting in the way of
science.
The ‘Positivist’ part of Logical Positivism was derived from
the work of August Compte, who had animus against traditional metaphysics. The ‘Logical” part of Logical Positivism came
from the belief in mathematical logic’s ability to
provide methods to build a new empiricism favorable to science and unfavorable
to metaphysics. Hume’s Fork heavily
influenced this version of empiricism: (1) the philosopher establishes the relations
of ideas, not matters of fact, and (2) philosophy clarifies linguistic problems
and establishes the relationship between statements and experience.
The principle of Logical
Positivism is as follows: every meaningful statement is either (1) analytic or
(2) makes a claim about experience.
Thus, there is a class of statements whereby we cannot say that they
contain any Truth. Imperatives and
questions have meaning but not in the empirical sense; they are not candidates
for Truth. Poetry and poetic statements
also do not aim for literal truth.
Analytic statements are true or
false based upon their meaning, but they have no factual content. Analytic
statements are knowable a priori: this means that empirical evidence is not
needed to establish their truth. For
example, no empirical evidence is needed to establish the truth of logical or
mathematical propositions. The power and
importance of analytic statements is that analytic
truths are necessary. For example, ‘No bachelor is married’ is true by definition. On the other hand, there can be a problem
with analytic statements; we may be certain that every effect has a cause, but this
certainty loses some of its importance if this assertion is merely based upon
how we use the words ‘cause’ and ‘effect.’
Kasser explains that classical
metaphysics is based upon facts, which makes them synthetic, but that the
metaphysics is supposed to be knowable independent of experience. Classical metaphysical claims hold no matter
what experience shows. Positivists claim
that a factual claim’s meaning is limited to its claims about possible
experience. Positivists claim that
metaphysical statements are not just merely true or false, but that they are incapable of bearing truth or
falsehood. Perhaps they are examples of
unintentional poetry, they speculate - cynically, perhaps.
Logical Positivists claim that a
statement must be true or false to be meaningful. This statement must also have a correct
method by which to determine whether or not it is true. Analytic statements use mathematical or
logical proof, which makes them verifiable.
If analytic statements can be linked correctly to a source, according to
linguistic rules, they are meaningful.
The concern within the Philosophy of Science is empirical statements,
which are not analytical, but synthetic.
Classical empiricism and operationalism focused upon connecting a
term to experience for verification, while the logical positivists
focused upon the meaning of a statement to connect it to
experience. This was a liberalization of
empiricism, which some advances in logic made possible. Using this method, a term gets its meaning
from making meaningful statements; a term does not need its
meaning independently established. Verifiability
of a synthetic statement involves finding possible
observations that support its truth. Actual
observations assess the truth of the
statement, not its meaningfulness. The difficulty is the requirement whereby
these observations are possible.
A set of possible observations
showing the conclusive truth of a statement is one way to ensure a statement’s
verifiability. This, however, may be
impractical. For example, establishing
the truth of “All copper conducts electricity” with a finite number of
observations is not possible. Some
Popper-influenced proposals substitute conclusive falsifiability with
conclusive verifiability. Combinations
of these two approaches face many counter-examples: unobservable objects are a
problem. “That streak in the cloud chamber
was produced by an electron” gets ruled out using these aforementioned
rules. If unobservable things get left
out using these rules, we need a more practical, and possibly a weaker rule. Ayer suggested that using a statement to derive observable
statements that cannot be derived within it may work. However, even this suggestion has problems;
it is too weak because it lacks restrictions on auxiliary hypotheses. For example, “If everything proceeds
according to God’s plan, then this litmus paper will turn pink when placed in
this solution” is an acceptable statement using Ayer’s suggestion. A modified suggestion on this approach is to
require the auxiliary hypothesis to be independently meaningful. Kasser claims that this suggestion succumbs
to technical objections.
These philosophical difficulties
to the Logical Positivist approach strangely did not affect Positivism’s
credibility. The idea to connect meaningful
statements to observation remained a powerful idea, but was tediously
difficult, if not impossible to adequately defend.
Commentary
The claims of the Logical
Positivists may sound good, but upon closer inspection, they do not survive
careful philosophical objections. It
seems that their assertions, and the accompanying claims to truth, are
presumptuous. The Problem of Induction
has been around for a long time, and the Positivist approach assumes that there
is no problem with induction. Perhaps,
they have ignored the problem of induction.
There is a serious problem with
all empirical claims, and this problem goes to the root of science. Defenders of science cannot ignore these
problems as irrelevant and go on in a stubborn fashion taking Positivism for
granted. To state it boldly, there seems
to be no way for the philosophical establishment of truth to a claim such as “All
copper conducts electricity.” This
objection is not necessarily fatal for science from a practical view. However, we must accept that this attack is
possibly fatal to the scientific claim to philosophical truth. It appears that many wish to establish
scientific truth on the same level as that of mathematics. This philosophical exercise shows that this
is not true – at least not yet.
This attack has implications
beyond science. In our court systems, in
legislation, and in the execution of law, we seem increasingly dependent upon
scientific experts. Science has a
privileged status in government and within law.
Also, there is the competition for funds from government, companies, and
many other organizations for the funding of scientific research. However, how can we justify this privileged
status when this claim to truth is in serious question? Why should science get more funding than the
humanities, literature, art, or even religion?
Why does it seem that science has a powerful privilege over these other
important areas of human nature? Who in
their right mind can claim that poetry has no serious meaning? Who will claim that great literature has no
meaning because it does not fit the positivist approach?
Perhaps the spectacular successes
of Newton, Einstein, and Maxwell provide a model of prestige that contemporary
supporters of science research wish to emulate.
This prestige gives an air of authority and supposed truth to all claims
of being “scientific.” Perhaps this
helps in raising funds for projects that otherwise would go unfunded. However, we astute observers of science (and
technology) must seriously question when this power over our institutions is
detrimental to other important areas of human inquiry.
