Tudománytörténet és Tudományfilozófia Tanszék
Eötvös Loránd Tudományegyetem
Budapest, Pázmány P. sétány 1/A

Tudományfilozófia Szeminárium

_____________________
2000, december


December 4. 16:00 6. em. 6.54
Kondor Imre
ELTE, Komplex Rendszerek Fizikája Tanszék
Alkalmazhatók-e az
elméleti 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 fizikusokat?
Mit csinálnak a fizikusok ezen a területen?
Milyen temákkal foglalkozik az "ökonofizika"?
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 hatását.
December 11. 16:00 6. em. 6.54
Bojan Borstner
 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.
1. Ontology
(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 of affairs
(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 or infinite.
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 relations. 
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.
3.52  Causation
There is a popular theory that defines causation as some sort of "necessary connection.
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 asymmetric.
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 asymmetric.
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 global; 
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 relation.
3.66  Causal explanation (why) is not reduced to nomological explanation (how).
  4. Conclusion
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. 
A szeminárium weboldala: http://hps.elte.hu/seminar
A szeminárium szervezõje: E. Szabó László