On 9th April 1996, Loren Haarsma wrote:
"Please note two important points:
1) "Observational science" fits somewhere between empirical and
historical science. It has some repeatability, but very little
control, explanatory links are expressed BOTH as causation and
natural law, it uses both abductive inference and induction, it
uses both observable and unobservable entities. Empirical &
observational science blend at the edges (difficult-to-control
systems), as do observational and historical science (rare
events).
2) [omitted]"
Apologies for the delayed response, but hope this still warrants
sharing.
Loren has summarised 5 characteristics of "observational science"
which make it an intermediate category between empirical and
historical science. I want to suggest reasons why we should
stick with just two categories.
It seems to me that any scientist who makes observations can
develop ideas (a) as to the operation of nature (empirical
science), and (b) the origin/past history of the observed
phenomena (historical science). The distinction between
empirical and historical is made in terms of what the scientist
is trying to do (what questions are to be answered). The
classification empirical/observational/historical seems to focus
more on methodologies in science. The overlap is only because
of the questions being asked.
It is a strange kind of empirical scientist who majors on
"observation" and avoids experimentation. Similarly, scientists
engaged in historical/origins studies will want to support their
observations with as much empirical work as they can - normally
employing the principle of actualism to develop explanations of
causation.
The only candidate for "purely" observational science I can think
of is cosmology, where the domain of interest is not accessible
to experimental probing. However, even here, I find it more
satisfying to consider the work of cosmologists as
(a) empirical (ie the present workings of the cosmos), and
(b) historical (ie the origin of the cosmos, galaxies, stars,
planets, etc.) The constraint on experimental methodologies is
a problem for cosmology - which results inevitably in a higher
degree of speculative and theoretical content than other branches
of science. This problem for cosmology need not be elevated to
a virtue by adorning it with the title "observational science".
To summarise: the empirical and historical distinctions arise
because of the different questions being asked and the inevitable
differences in methodology required to find answers. The
suggested category of "observational science" involves no new
questions, no new methodologies, and its intermediate status is
an illusion - because both empirical and historical science
utilise observations extensively. The more science is limited
to observations, the more open-ended it becomes, and the greater
is the opportunity for poorly-constrained theoretical and
speculative work.
If Loren (or anyone else!) wants to defend "observational
science", I will be interested to hear. Obviously, it is
important for understanding what science is about, what
methodologies are appropriate, and assisting debates about
origins.
Best wishes,
*** From David J. Tyler, CDT Department, Hollings Faculty,
Manchester Metropolitan University, UK.
Telephone: 0161-247-2636 ***