Reduction and Elimination in Philosophy and the Sciences

assumptions. Loewer argues that notion of the natural law
in scientific practice does not require the governist idea
that laws have to govern events so it is right to abandon
governism. However, Balashov (2002) as a non-humean
can also appeal to scientific practice in order to show that
humean solutions are untenable. He argues that laws can
be strongly supported by empirical evidence and have
explanatory power only if they are necessary. It is clear
that what Balashov has in mind is the concept of mindindependent
natural laws which can be discovered with the
help of our science.
I think that without a sharp distinction between notions
of natural laws and scientific laws, it is impossible to
see the problem as clearly as we need. The concept of
natural laws involves universality, so “laws of nature without
universality” is a contradiction while there is no such a
contradiction in the sentence that “the laws of thermal expansion
is not universal”. This can be demonstrated easily:
if ΔL = k.L0 .ΔT were an universal truth it should be impossible
to cite situations where the relation between L0, ΔT
and ΔL falls, but there is an infinite number of provisos
implicit in a statement like “without hammering the heated
iron rod inward at one end ...”, so it is impossible to state a
genuine law-statement. Thus scientific laws cannot be
universal, while implicit in the concept of natural laws we
presuppose universality. scientific laws – at least most of
them – certainly fail to being equal to natural laws.
A metaphysically moderate version of
Humean Supervenience
I am agnostic about the feasibility of metaphysical approaches
so I will focus on the question of scientific laws
instead. As I said scientific laws – or at least lots of them –
fail to be universal. What more can we say about scientific
laws? Earman and Roberts (2005) identify laws with
mathematical treatments of certain problems. They wrote:
“In modern physics (by which we mean, at least, physics
since Newton), the typical form of a problem is that of solving
a differential equation (or a system of such equations)
subject to certain boundary conditions, which typically
include initial conditions.” (Earman & Roberts 2005, 13).
The difference between nomic and non-nomic facts is
merely a methodological one. We have to distinguish
boundary and initial conditions and equations while we try
to solve a problem, but this difference is not ontological.
This definition restricts the field of scientific laws to laws
which can be formulated mathematically. Thus if we hold
this view as an appropriate account of scientific laws, we
cannot count many of scientific generalizations as laws;
e.g. laws of biology will be non-laws according to this
analysis. I do not think that this would be the right move.
However, implicit in the view presented by Earman and
Roberts (2005) there is something resembling to Hume's
original insight, that nomic relations among events is not
observable. They define the Humean base as follows: “The
Humean base at a given world is the set of non-nomic
facts at that world that can be the output of a reliable, spatiotemporally
finite observation or measurment procedure.”
(Earman & Roberts 2005,17).
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A Metaphysically Moderate Version of Humean Supervenience — Szilárd Koczka
Earman and Roberts suggest a modal
characterization of HB. In the light of their analysis a fact
belongs to the HB if and only if there is a nomologically
possible observaiton or measurement procedure to detect
it. The explanation will be circular only if we interpret
nomological possibility as a mind-and-theory independent
feature of our world. I prefer the alternative – ontologically
less committed – interpretation that something is
nomologically possible if it is compatible with our scientific
laws. It is an epistemological characterization of
nomological possibility and it has its own problems, but I
think this is the best we can offer. There is a bit obscure
notion within the definition presented by Earman and
Roberts, namely reliability. To disperse this obscurity I
define reliability as follows: An observation or
measurement procedure can be reliable, if it is consistent
with our already accepted theories and all observable fact.
In addition, reliability has a normative feature: what is and
what is not reliable depends on our current theories. This
normative feature can be understood with the help of
Kuhn's (1996) terminology. Even if it is incorrect to talk
about “Scientific revolution”, the core idea that scientific
standards can change with paradigms seems plausible
enough. Thus I refine my definition: A measurement
process is reliable, if it is consistent with our already
accepted theories and directly observed facts, and it fits to
our current scientific standards.
A moderate version of Humean supervenience as a
minimalist theory states that we can develop predictable
useful scientific laws as inference rules that belongs to
certain models or systems. The models we develop are
useful instruments of explanation and prediction, but we
can never be in an epistemological position that enables
us to declare that in scientific research we can discover the
mind-and-theory independent natural laws. We have an
ability to perceive relevant patterns of non-nomic facts,
there by creating instrumentally useful models or systems,
rather than the very natural laws. The Humean Base
consists of facts that we can acquire directly or with the
help of any reliable observational or measurement
procedure. One can argue, that the moderate version of
HS is not the same as that of Lewis elaborated, and it is
obviously true. Why call this thesis Humean
Supervenience after all? Lewis dedicated his thesis as “in
honor of the greater denier of necessary connection”(Lewis
1986,ix), however it is possible to come up with a
supervenience thesis about laws which can express
Hume's original – epistemological – motivations about
nomic relations.