Lecture One Epistemology and Economic Methodology

Epistemology Questions: Does an objective reality exist that is independent of our thinking? Do ultimate truths describe that reality?

Epistemology Propositions Realism: Yes, objective reality exists –Absolutism: Yes, ultimate truths describe that reality –Relativism: Objective reality may exist, but truths describing it are relative to circumstances –Example of difference: Usury debate Subjectivism, Postmodernism: No, reality is not independent of our individual or social thinking

Methodology Defined: Technique for discovery of knowledge. Assumes that an objective reality does exist, and it can be explored. Methodological questions: What is science? What are the proper roles of scientists? What mix of empirical observation, logical analysis, and intuitive insight is best used to strengthen our understanding of reality?

Methodological Approaches Deductive Method General propositions (positive or normative) lead to specific logical implications Early Practitioners/Proponents: Aristotle (400 BC) David Ricardo (1817)

Methodological Approaches Inductivism, Empiricism From specific observations, rooted in experience, to general conclusions Proponents: John Locke (1690) Auguste Comte--(Positivism) Carnap & “Vienna Circle” (1920s-30s)--Logical Positivism Karl Popper ( )—Falsificationalism Thomas Kuhn (1962)--Scientific Revolutions; Competing Paradigms

Positivism & Logical Positivism Positivism (Comte, Hume, J.S. Mill, 19th Century) Science can rise above superstition by specializing in the description and analysis of observable phenomena, leading to discovery of natural laws. Logical Positivism (Moritz Schlick and Rudolf Carnap, 1930s) Science progresses toward truth by observation, formulation of hypotheses, empirical verification, leading to additional hypotheses Distinction between positive (scientific) and normative (unscientific) questions

Karl Popper: What is a Science? Philosopher writing at time of collapse of Austro- Hungarian empire ( ) Once convinced, then disillusioned by Marxist theory of history Characterises these, psycho-analysis, astrology, etc. as “pseudo-science” Posed question: “'What is wrong with Marxism, psycho-analysis...? Why are they so different from physical theories...?'... these... theories, though posing as sciences, had... more in common with primitive myths than with science...” [Conjectures & Refutations]

Karl Popper: What is a Science? Rejected conventional explanations (empirical inductive method) because pseudo-sciences (e.g. astrology heavily “empirical”) Noticed characteristic of pseudo-sciences: confirmation –“admirers... were impressed... by their apparent explanatory power. These theories appeared to be able to explain practically everything that happened within the fields to which they referred…” “A Marxist could not open a newspaper without finding... confirming evidence for his interpretation of history;... in the news,... its presentation …and especially of course in what the paper did not say.”

Karl Popper: What is a Science? Argued that confirmation meaningless: “every conceivable case could be interpreted in the light of [the relevant] theory”: they could not be refuted Therefore, by exclusion, a true science was one which could be refuted Every 'good' scientific theory is a prohibition: it forbids certain things to happen... A theory which is not refutable by any conceivable event is non-scientific... Every genuine test of a theory is an attempt to falsify it, or to refute it...

Popper’s Continuing Influence: George Soros “Popper showed that totalitarian ideologies like communism and Nazism have a common element: they claim to be in possession of the ultimate truth,... juxtaposed with... another view of society, which recognizes that nobody has a monopoly on the truth; different people have different viewsand different interests, and there is a need for institutions that allow them to live together in peace..” Reflexivity: “Why does nobody have access to the ultimate truth? The answer became clear: We live in the same universe that we are trying to understand, and our perceptions can influence the events in which we participate. If our thoughts belonged to one universe and their subject matter to another, the truth might be within our grasp: we could formulate statements corresponding to the facts, and the facts would serve as reliable criteria for deciding whether the statements were true.” “Whether the theory is valid or not, it has turned out to be very helpful to me in the financial markets.”

Popper’s Continuing Influence: George Soros “Insofar as there is a dominant belief in our society today, it is a belief in the magic of the marketplace. The doctrine of laissez-faire capitalism holds that the common good is best served by the uninhibited pursuit of self-interest. Unless it is tempered by the recognition of a common interest that ought to take precedence over particular interests, our present system -- which, however imperfect, qualifies as an open society --is liable to break down.” “I want to emphasize, however, that I am not putting laissez-faire capitalism in the same category as Nazism or communism. Totalitarian ideologies deliberately seek to destroy the open society; laissez-faire policies may endanger it, but only inadvertently. Friedrich Hayek, one of the apostles of laissez-faire, was also a passionate proponent of the open society. Nevertheless, because communism and even socialism have been thoroughly discredited, I consider the threat from the laissez-faire side more potent today than the threat from totalitarian ideologies.”

Popper’s Continuing Influence:Baylor Controversy 14/feature2.html/printable_pagehttp:// 14/feature2.html/printable_page Is Intelligent design theory a science? William Paley (18th-century British natural theologist): Living organisms are more complicated than watches "in a degree which exceeds all computation," therefore we too must be the products of some grand watchmaker, an intelligence.” Dembski: Science of revealed intelligence—complexity and specificity Charles Weaver: “"You can always look at something and say, "That's something that God did,' " says Weaver. "Well, what can I do to prove you wrong? If I can't prove your theory incorrect, it doesn't necessarily mean that it's wrong, but it means it's not science."

Thomas Kuhn: Paradigms Scientific community wedded to its view of the world--its paradigm Anomalies--things which contradict theory--at first resisted Failure to resolve leads to revolution--often from outside Switch to new paradigm involves total change in “world view” Lakatos: Methodology of Scientific Research Programs (MSRP) –Theories have “hard core” which adherents do not attempt to falsify –Hard core surrounded by “protective belt” of hypotheses which may be adjusted to defend hard core

What is a Good Theory? Milton Friedman –Proper test of a theory is by its predictions –All theory is abstraction. Good theory “abstracts from reality in a useful way.” –“Realism” of assumptions irrelevant: “the more significant the theory, the more unrealistic the assumptions… a hypothesis is important if it ‘explains’ much by little” “as if” assumptions--firms behave “as if” maximising expected returns, etc.--valid even if firms do not consciously do so. Paul Samuelson: Good theories are based on reasonable assumptions—against the “F-Twist”