Research Methods

Lecture 2: Positivism, its variants and its impact on Economics

Why study Positivism?

• Hughes & Sharrock (1997: 24): positivism was ≈ orthodoxy in social science

• No longer believed? (Williams, 1976)

• Yet economics still heavily influenced

• Authors defined in terms of positivism

• Positivist tools (e.g. survey) still dominate

• Must try to give it a fair hearing!

Roots of positivism• Renaissance/Enlightenment thought of

16th/17th Centuries• Philosophy divided into empiricism/

rationalism: foundation of knowledge experience/reason; Bacon/Descartes

• Saint-Simon: liberate people from dominant ideas; French Revolution

• Get past illusions to “social facts” (Durkheim)

Comte’s positivism• Influenced by Hume’s attacks on

metaphysics

• Two bona-fide forms of knowledge: empirical and logical, but empirical emphasised

• Precision, clarity and certainty

• View world as machine (reflects Descartes)

• World comprises deterministic laws, regularities; waiting to be discovered by the scientist

Positivism: basics

• Laws: whenever A, then B (plus CP)

• Causality: constant conjunctions of events (Hume)

• Single cause leads to single effect (Durkheim)

• Mill’s tendency statements, Hume’s caution both too weak for modern positivists

Scientistic naturalism

• Social science should imitate natural sciences (although why? Never stated!)

• Aim for “unity of method”

• Differences acknowledged between subject matters

• Science proceeds via observation, modelling, to get to laws

Observation• “Brute facts” (not affected by any judgement):

mimic natural sciences (e.g. atom, velocity)• Observation is preconception free (Durkheim) and

Value-free (positive analysis)• Correspondence theory of truth• Variables; measuring properties present in entities• Quantification: counting frequency of some

property present in some entity• Operationalism: object defined in terms of the

means of measuring/checking it (Hausman: 14)

Theory development

• Individualism; reductionism

• Modelling

• Testing predictions of models

• Verification

• H-D model tries to solve problem of induction

Logical positivism

• Carnap, Mach (Vienna Circle), Ayer, Russell: trying to make positivism more logical

• Meaningful (True) statements must be verifiable

• But now analytic statements can be true by virtue of the logical rules by which they are deduced

• Yet LP questioned ‘ideal types’

Popper’s intervention

• Karl Popper: capturing spirit of positivism in many ways but opposite in others

• Sceptic: verification impossible

• No theory proven; yet to be falsified

• “Scientific” theories are testable

• Theories set up bold conjectures to be tested

• Test theories by their predictions

Popper’s intervention

• Falsification from a single counterexample

• Learning by trial and error

• Idealised view of science

• Kuhn, Lakatos: Popper underestimated tenacity with which “failed” theories are retained

• Kuhn: sciences proceed irrationally; normal vs. revolutionary science

Friedman (1953)

• Highly influential essay

• Can be interpreted as combining elements of positivism with Popper

• “positive economics”

• Purpose of theory = prediction

• Good theories predict well

• Simplicity and precision also good

Friedman

• Assumptions of theories not important• Assumptions are always simplifications -

cannot be “realistic” - cannot assess theory via “realisticness”

• Assumptions are shorthand for conditions, etc. under which theory works

• Model works “as if” assumptions are correct: e.g. mobile leaves; profit maximisation

Conclusions

• Positivism has had several highly significant effects on economics:

• Mimic natural sciences• “Value-free” analysis• Causal laws: “if X then Y” type• Quantification • Tools used• Emphasis on deductive logic

Conclusions

• H-D model• Friedman also very influential• Assertions about “positive” economics, the role of

assumptions, prediction and falsification (echoing Popper) adopted strongly (at least “officially”)

• Both subject to considerable criticism• Next two lectures will engage criticisms of

positivism and its variants