és Tudományfilozófia Tanszék
Pázmány P. sétány 1/A
||6. em. 6.54
ELTE, Komplex Rendszerek Fizikája
fizika módszerei a pénzügytanban?
Az elõadás a következõ
kérdéseket kivánja körüljárni:
Hogyan és miért alakult
ki az a helyzet, hogy a fejlett világ pénzügyi intézményei
az elmúlt tíz évben egyre nagyobb számban alkalmaznak
Mit csinálnak a fizikusok ezen
Milyen temákkal foglalkozik az
Mennyiben állithatók a piacok
a fizikában vizsgált "komplex rendszerekkel" analógiába,
és milyen mértékben alkalmazhatók a fizika
módszerei a leírásukra?
Az elõadás végén
illusztrációként röviden elemezzük a racionális
portfólióválasztás Markowitz-féle elméletének
és az opcióárazás Black-Scholes-féle
elméletének a piacok fejlõdésére gyakorolt
||6. em. 6.54
Department of Philosophy, University
of Maribor, Slovenija
STATES OF AFFAIRS, UNIVERSALS
AND SINGULAR CAUSATION
|In this lecture we search for a theory that will (at least implicitly)
define the concept of causation.
(i)The world contains a number of individuals. Individuals are first
order particulars, which are things taken along with all their properties.
(ii) Properties and relations are fundamental constituents of the world.
What properties and relations there are can not be determinate a priori,
but a posterior, empirically, on the basis of total science.
(iii) Properties and relations are conceived of as universals.
(iv) Individuals, properties and relations are constituents of states
(v) There are complex and simple properties.
(vi) Complex properties have constituents that are:
(a) not ultimate - complexity
without simple constituents
(b) Ultimate - simple properties
that are finite or infinite in number - complexity may be finite
2. Theory of causation
2.1 We search for a theory that will (at least) implicitly define the
concept of causation. Our goal is not the theory that is just contingently
true. A theory of causation must be analytically true and it must offer
an analysis of the concept of causation that must be true in all possible
worlds (not just in actual).
2.2 Hume, in the Treatise, famously offered consecutive pairs of definitions
of causation (Hume, 1975, 170)
2.3 The conclusion that we can derive from Hume's ideas is:
(i) causation is not directly observable
(ii) causation can not be a primitive relation between events
(iii) therefore, causation is reducible to some other items (in Hume's
case to the contiguity and precendency)
3. Basic features
3.1 A causal relation is any relation between states of affairs
that is irreflexive and asymmetric, which excludes loops, and which satisfies
the open sentence T.
3.2 Some relations between states of affairs are genuine
3.3 No relation relates less than two particulars - no particulars
can be related to itself.
3.4 All genuine relations are necessarily irreflexive:
3.5 If a causal relation is not necessarily antysymmetric then there
is no distinction between a causal relation and nomic necessity.
3.51 Nomic necessitation:
(i) it is a law that anything with property
F also has property G. The first thesis is compatible with: it is a law
that anything with property G has property F.
(ii) If having property F is causally
necessary for having property G, it must be a law that whatever has property
F has property G.
(iii) If having F is causally sufficient
for having G, it must be a law that whatever has G also has F.
(iv) If having F is both causally necessarily
and causally sufficient for having G, it must be a law that something has
property F if and only if it has property G.
(v) Therefore, the relation of nomic
necessitation cannot be necessarily asymmetric.
There is a popular theory that defines causation as some sort of "necessary
3.521 Causal relation:
(i) if SOA S causes SOA U it cannot
be the case that U causes S.
(ii) causal relation is necessarily
3.522 Causal necessitation:
(i) If having property F is a causally
sufficient condition for having property G, then having property G cannot
be a causally sufficient condition for having property F.
(ii) If having F is causally sufficient
condition for having G, then having G is causally sufficient condition
for F iff G is identical with F.
(iii) causal necessitation is necessarily
If a relation R is a causal relation then it is asymmetric,
transitive and irreflexive.
3.6 Laws of nature and causality
Laws are second order state of affairs. They involve relations between
universals, which nomically necessitate corresponding statements about
first order particulars (SOA)
3.61 Causal laws are laws that involve causal relations.
3.62 Causal laws and necessary and sufficient conditions are
causal relation is local.
3.64 The existence of a causal relation does not by itself guarantee
the existence of a law.
3.65 Causal explanation subsumes SOAs (events) under the causal
3.66 Causal explanation (why) is not reduced to nomological explanation
If the singularist theory of causation is correct then it is logically
possible for there to be causally related SOAs that do no fall under any
law and it is possible to explicate the theory of causation without any
reference to laws of nature. However, it does not exclude the possibility
that there are laws of nature and singular causal relation could be an
instantiation of such a law.