Prelude
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This page is taking me a while to get into a satisfactory state, and its not
there yet.
This is exacerbated by my having only in the last day or two decided that what
I should say about positive science in the context of metaphysical positivism
lack normative of prescriptive content.
I'm looking to restructure this page so that there is some historical
background which reflects the normative origins of the concept, but that
the substance of the account should be a description of the opportunities for
logical analysis in science leaving open the question of when these
opportunities may be worth taking up.
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Summary
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Our positive science is neither inductivist, falsificationist, verificationist nor
scientistic.
It is based on the idea that positive science consists in the construction of models of
aspects of reality, in theoretical and experimental evaluation of the models
and in the presentation of the results of these evaluations.
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This conception of science is neither descriptive nor prescriptive.
It is constructive, analytic, and discretionary, i.e. we put forward the ideas,
consider their merits and weaknesses, and speculate about their scope of application.
Scientists may or may not find any of this interesting or useful.
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Our positive science involves is not phenomenalistic, reductionist,
verificationist, falsificationist.
It is pragmatic, but does not have a pragmatic attitude towards truth, and it
is not enthusiastic about, induction, confirmation theory, verisimilitude or
other ways of quantifying closeness to truth, or even about the idea that
scientific theories are ever "true".
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It may be argued that fundamental theories in physics go beyond the facts in various ways.
We discuss here some ideas about how they do that and how one might attempt to separate out the hard content of a theory from
these more difficult areas.
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Scientific theories present models of aspects of reality which are not true or
false but are evaluated in term of their scope of applicability, accuracy and
reliability.
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Positive science is the application of formal analysis to empirical science.
We do not wish to overstate the scope of such applications, and recognise the
possibility that valuable scientific results might be obtained whose character
defies formal analysis.
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Transforming Positive Science
The position of our Positive Science may be thought of as arising from two
kinds of adjustment to more traditional positivistic (and related, such as
pragmatist or deductivist) ideas.
There are:
- Elimination of Negative Dogma
- Exploitation of Analytic Method
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Elimination of Negative Dogma
The most significant negative dogmas of positivism arise from the denial of
inference from sense data to the external world, and it is this which leads to
phenomenalism.
Though our conclusions about the external world may not be demonstrable, this
does not necessarily or even probably, mean that they are false.
The inference from present or past phenomena even to future phenomena is no
more sound than the inference to the existence of material objects, or to
general scientific laws involving such objects.
But if the phenomenal inference were eliminated then science could serve no purpose.
The idea that a scientist should do no more than describe what he has observed
of the world can be squared with the formulation of general laws of physics by
allowing that the experiments be oriented towards evaluation of such laws and
experimental results should be presented comprehensively in the light of their significance to that end.
Phenomenalism, verificationism, falsificationism are all negative dogmas in all
their variants and ideas like confirmation theory and verisimilitude and its
successors are primarily motivated by the attempt to ameliorate the defects of
the negative dogmas.
Reductionism, when inspired by these dogmas is likely to be defective, but in
general, when pragmatically inspired, may be useful.
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Exploitation of Analytic Method
The Positivistic idea that civilisation progresses, and that this is connected
with the evolution of epistemological standards (how truth is established) is
retained, and one further stage in this process is the enabling of logical
analysis.
The idea here is that the formalisation of science enables rigorous formal
analysis, possibly computer assisted.
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Positive Science
I'd like to mention first, to put this discussion into philosophical context, the notion of "positive science" which originates
with Comte and has variants in many kinds of positivism.
In David Hume we see first the praise of science and the castigation of metaphysics.
In Comte we see an awareness that not all that passes for science is good (some entire disciplines are regarded by him as
worthless), and that even in domains which are productive, the manner of doing science and the conclusions which scientists
draw may be inappropriate.
In positive science the scientist is engaged in undertaking experiments and in reporting the results of his experiments.
His theories should not go beyond the experimental data, they should merely summarise it.
What I want to do here is keep this idea in mind, but moderate it somewhat so that we end up with some sense of how a theory
of physics may go beyond its experimental mandate, discover some way to separate out the definite from the speculative, and
then consider ways in which the issues which then remain uncertain can be progressed.
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Moderating Positivism
I don't know exactly what Comte had in mind when he talked about theories not going beyond the experimental data on which
they are based, but there is one very basic way in which we do normally expect them to do so.
We expect a scientific theory to be a generalisation, of which the experimental observations provide particular instances.
The merit of such a theory lies precisely in its going beyond the experimental observations to tell us what the results would
be if many other similar experiments which fall within its scope.
A second way in which positivists seek to limit science is phenomenalistically.
Thus, one approach to formalisation of physics attempted by Carnap and others in the most recent major phase of positivism
was to do so using a language which spoke only of the phenomena or sense data.
This is not what I have in mind here.
We need to think and talk about the things which cause these phenomena.
The Logical Positivists had another approach to separating science from metaphysics.
This was to be liberal about the language of science but insist that a theory be empirically "verifiable".
They ultimately failed to define this notion in a satisfactory way, but even if they had succeeded it would not suffice for
my present purposes.
For this tests the theory as a whole and I am interested in taking a single theory, say for example General Relativity, and distinguishing physical content from
verbal or metaphysical content.
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Positivist Residue
What remains may not qualify as positivist, it is so only in the limited sense of recognising that there may be differences
in the character of different aspects of a physical theory which allow further discussion of certain aspects of a physical
theory which has solid observational support.
The distinctions include something which might reasonably be described as the distinction between physics and metaphysics,
though in this case the attitude towards the metaphysics is not so negative as is typical for positivists.
I cannot offer any kind of definition of the distinctions which are at stake here, it is part of the enterprise to make the
distinctions clearer, but I have no expectation that they will become sharp.
The distinctions of interest here are between physical and verbal content (in which no great weight should be attached to the word "verbal") and that between metaphysical and other content.
Historically it is natural to think of the structure of space and time as metaphysics.
In the twentieth century they have come to be viewed as physics, because first special and then general relativity put forward
theories which depended upon changes to our ideas about space and time, and turned out to be better models of physical reality.
However, though the theories are better models than their predecessors, there may be alternatives which are equally good in
accounting for the observational data but which do not involve changes in our conception of space and time.
In the case of special relativity, there are equivalent theories which retain Newtonian space-time and are equally consistent
with experimental data.
I'm not intimate enough with the detail but lets suppose that Newtonian mechanics with absolute motion and a lorentz contraction
on bodies according to their absolute velocities is one such theory and call it NFL.
Not sure whether there is a stronger relationship between SR and NFL that their joint consistency with the empirical data.
Suppose that they are equivalent in a strong way.
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Platonic Precursor
I have come to the opinion that my own conception of positive science is closer
to Plato than it is to Comte!
In Plato we have knowledge only of forms, we have opinions about the material
world (world of appearances) but the things we find there are approximations to
the Platonic forms, the correspondence is never exact.
Hume also held that we have knowledge only of relations between ideas, not of
the material world, so there is a positivist connection.
However, he accepted that people would, from habit, form beliefs about the
material world by inference from the evidence provided by our senses, and
sought in his sceptical arguments either to constrain those inferences or to
interpret the conclusions in ways less distant from their evidential basis.
This leads to the negative dogmas of phenomemalistic metaphysics.
The conception of positive science proposed here is similar to Plato and Hume
in admitting certain knowledge only of logical or mathematical truths.
We advocate that scientific theories be presented as abstract models of reality
which are probably never exact, and in any case could never be known with certainty to be
perfect even if they were.
Instead of claiming that a scientific theory is "true" we should instead offer
it as an imperfect model, and provide information about the areas in which it
is thought to be applicable and its accuracy and reliability in those areas
(though there is a problem of regress here, are these claims to be considered
true or false?).
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The conformity with Plato is incomplete.
For Plato, the world of forms, which corresponds in our analogy to the domain
of abstract models, is "real" and the physical world is illusory.
In our conception, the physical world is real, the abstract models are more
like logical fictions.
Plato considered things in the real world to be imperfect copies of the forms.
By contrast we see the abstract models as idealisations of or approximations to
aspects of the real world.
On the face of it these differences might be purely verbal, however, there are
fundamental methodological differences which connect with these different
viewpoints and prevent them from being purely verbal.
This corresponds roughly to the idea that Plato is a rationalistic
metaphysician, whereas our position is closer to the modern conception of
empirical science.
In Plato's case the forms are discovered by the philosopher by contemplation or
dialectic, in our case the abstract models are constructed to provide a good
model of the physical world.
Observation and experiment are relevant to obtaining a good match, and a
crucial part of positive science.
For Plato, the imperfect resemblance of the real world to the forms is not a
point of central concern.
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Abstract Modelling
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Not true or False
If we look objectively at scientific laws and ask whether they are literally
and precisely true, then we find good reason for doubt.
However, even in the many cases where the laws are known to be only
approximations, they may nevertheless be of the greatest practical utility.
Newtonian physics is a good example of this.
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Some Implications of Falsity
If scientific theories are normally idealisations or approximations rather than
literal truths, then decisive verification is impossible and falsification too
easy to warrant rejection.
Confirmation theory no longer makes sense (for what is the point in assessing
the probability that a theory is true if we accept that it is in fact false?).
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Abstract Models for Nomologico-Deductive Science
If, instead of talking about the truth or falsity of scientific theories, we talk
about the characteristics and utility of scientific models, then our language
becomes less dogmatic, more flexible, and potentially more informative.
Typically, scientific law are mathematical in character.
Talk of abstract models is helpful in rigourising this.
The idea is that the nomological part consists in the construction of an
abstract model of some aspect of reality, and the deductive part consists in
the logical analysis of the model and its application to specific circumstances.
We neither claim to infer to the model from observations, nor to attempt its
falsification.
Instead we use observations to gather data on the scope of applicability of the
model, and present this data both in summary and detailed forms.
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Analysis not Prescription
Positivist philosophies, and similar kinds of philosophical system such as
critical rationalism, tend to result in prescription or proscriptive
demarcation lines, which generally prove controversial and rarely reflect the
practice of science or any probable amendment to it.
What I offer here is a method for consideration on its merits.
I believe that possible benefits may flow from the conduct of science along the
lines hinted at here, and advocate further investigation of that possibility.
However, we have no inclination to prescribe the method, or to proscribe
science conducted by other means.
There is a question which might be considered, whether a scientific theory
which, for some reason, could not possibly be captured in an abstract model
should be considered part of science.
This is not a question which I intend to consider.
There is a related question which is of much greater interest to me, viz. how
might it be possible for some supposed knowledge to be both useful and in
principle unformalisable.
In relation to this question a matter consideration is that vast realm of
knowledge which consititutes sound judgement in various domains of expertise.
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