||A philosophy of science developed by Karl Popper, originally as a critical response to the logical positivism of the Vienna Circle. (Neurath, a member of the Circle, nicknamed Popper \'the Official Opposition\'; see Popper, 1976.) Popper\'s philosophy is wide-ranging, and detailed discussions have been provided by Burke (1983) and O\'Hear (1980), but two connected components have been of special significance for human geography.
The principle of falsification. In The logic of scientific discovery (1934; translated into English in 1959) Popper challenged the \'principle of verification\' which was at the heart of logical positivism by suggesting that \'not the verifiability but the falsifiability of a [theoretical] system\' should be taken as a \'criterion of demarcation\' between the empirical sciences on the one hand and mathematics, logic and metaphysics on the other. This was not the same as a criterion of meaning, Popper emphasized, because \'falsifiability separates two kinds of perfectly meaningful statements\': a view which made him still further at odds with the Vienna Circle who regarded metaphysics as scientifically meaningless. Within human geography, Wilson\'s (1972, p. 32) programme for a \'theoretical geography\' was explicitly based on Popper\'s procedures:
The essence of the scientific method is the construction of theories and the continual testing of these by comparing them with observation. The essence of such testing is an attempt to disprove a theory â€” to marshall observations which contradict the predictions of the theory. In this sense, theories are never proved to be generally true. The ones in which we believe represent the best approximations to truth at any one time â€¦ We expect, then, that theories will be subject to constant development and refinement: sometimes a falsified theory can be patched up; sometimes, radically different theory is needed.As the last sentence implies, Popper\'s principle is often methodologically intractable, whatever its logical attractions. Even though Popper himself recognized this and attempted to stipulate a number of safeguards against ad hoc tinkering, Sayer (1992) dismisses the principle of falsification as \'virtually impossible to put into practice\' (cf. Marshall, 1982 and Hay, 1985). It is certainly the case that the principle has rarely been used in human geography, even at the height of spatial science, but, as Wilson (1972) noted, this was as much a result of the inductivist bias of the quantitative revolution as any considered rejection of critical rationalism. (This never prevented some quantitative geographers from using Popper to object to Marxism because, according to Popper (1945), it either cannot be falsified, or has been falsified and hence loses any claim to be a \'science\'.)
The progress of science. Popper used the iterative sequence described by Wilson (above) to argue, further, that \'the growth of knowledge\' depends upon a method of \'rational criticism\'. He usually represented it like this: Â P1 â†’ TS â†’ EE â†’ P2
Thus, we are supposed to start from a problem (P1), then formulate a trial solution (TS) \'which we then subject to the severest possible test [that is, falsification] in a process of error elimination\' (EE), which in turn leads to the creative formulation of a new problem (P2). Hence, in Popper\'s view, the progress of science depends upon a creative response to error â€” upon what he called Conjectures and refutations (1963). Many commentators, and Popper too, have contrasted this normative model with Kuhn\'s account of the changing structure of scientific knowledge (see paradigm). So, for example, Bird (1975) correctly recognized that \'the implications for geography to be drawn from Popper\'s works are quite different from those to be drawn from the writings of Thomas Kuhn\'. And Marshall (1982), although he mistakenly assumes Kuhn to stand \'in the mainstream of the logical positivist tradition\' by virtue of the very tactic which Popper (1976) rejects (namely judging books \'by their covers or editors\'), urged geographers \'to look elsewhere if [they] are concerned to understand the logic of the process by which knowledge advances\' (i.e. Popper) rather than \'the sociology of academic life\' (i.e. Kuhn). Kuhn\'s whole object was indeed to confront what Barnes (1985) terms \'the myth of rationalism\' on which Popper\'s project is founded. Barnes provides a number of general reasons why rationalism might properly be called a \'myth\'; but perhaps the most telling specific objection comes from Sayer (1992, p. 230): \'What do we learn when a deductive theory is legitimately falsified? â€¦ Only that we must try a different deductive theory â€¦ only that something is wrong and not what is wrong\'. The essential weakness, Sayer contends, is that â€” unlike Sayer\'s preferred philosophy of realism â€” Popper\'s strategy \'ignores the content of theory\' and so is incapable of distinguishing causal explanation from instrumentalist \'deviation\' (see instrumentalism).
But Chouinard, Fincher and Webber (1984) used Imre Lakatos\'s critique and reformulation of Popper\'s proposals to argue that it is possible to conduct scientific research programmes in human geography in ways which are none the less conformable with realism. Lakatos (1978) believed that Popper was too ready to reject theories and argued for a more cautious, \'conservative\' strategy: in his view, scientific progress ought to depend on the careful evaluation of what he called problem-shifts. A series of scientific theories is to be counted as theoretically progressive \'if each new theory has some excess empirical content over its predecessor, that is, if it predicts some novel, hitherto unexpected fact\', and as empirically progressive if some of this excess empirical content is also corroborated, that is, if each new theory leads us to the actual discovery of some new fact\'. Unless a problem-shift satisfies both of these conditions it will be degenerating rather than progressive and ought not to replace the existing formulation (Lakatos, 1979). In much the same way, Chouinard, Fincher and Webber (1984, p. 375) argued that:
It does not make sense, when dealing with an open system and therefore with a reality without invariant cause and effect relationships, to reject one\'s core propositions about causal mechanisms and processes only because of apparently disconfirming empirical evidence. Instead, the criteria for accepting or rejecting a particular research tradition in human geography must be programmatic, that is, they must evaluate the coherence and creativity of a particular approach in terms of expansion in the conceptual and empirical scope of explanation.Be that as it may, Lakatos\'s proposals are not immune to objection (Barnes, 1982) and it is by no means clear that, even in this revised form, \'the critical rationalist viewpoint can provide a new and welcome coherence\' in human geography (Marshall, 1982; cf. Bird, 1989).Â (DG)
References Barnes, B. 1982: T. S. Kuhn and social science. London: Macmillan.Â Barnes, B. 1985: Thomas Kuhn. In Q. Skinner, ed., The return of grand theory to the human sciences. Cambridge: Cambridge University Press, 83-100.Â Bird, J.H. 1975: Methodological implications for geography from the philosophy of K.R. Popper. Scottish Geographical Magazine 91: 153-63.Â Bird, J.H. 1989: The changing worlds of geography. Oxford: Clarendon Press.Â Burke, T. 1983: The philosophy of Popper. Manchester: Manchester University Press.Â Chouinard, V., Fincher, R. and Webber, M. 1984: Empirical research in scientific human geography. Progress in Human Geography 8: 346-80.Â Hay, A.M. 1985: Scientific method in geography. In R.J. Johnston, ed., The future of geography. London:Methuen,129-42.Â Lakatos, I. 1978: The methodology of scientific research programmes. Cambridge: Cambridge University Press.Â Lakatos, I. 1979: Falsification and the methodology of scientific research programmes. In I. Lakatos and A. Musgrave, eds, Criticism and the growth of knowledge. Cambridge: Cambridge University Press, 91-196.Â Marshall, J. 1982: Geography and critical rationalism. In J.D. Wood, ed., Rethinking geographical inquiry. Downsview, Ontario: Department of Geography, Atkinson College, York University, 73-171.Â O\'Hear, A. 1980: Karl Popper. London: Routledge and Kegan Paul.Â Popper, K. 1945: The open society and its enemies. London: Routledge and Kegan Paul.Â Popper, K. 1959: The logic of scientific discovery. London: Hutchinson; New York: Basic Books.Â Popper, K. 1963: Conjectures and refutations: the growth of scientific knowledge. London: Routledge and Kegan Paul.Â Popper, K. 1976: Reason or revolution? In D. Frisby, ed., The positivist dispute in German sociology. London: Heinemann; New York: Harper and Row, 288-300.Â Sayer, A. 1992: Method in social science: a realist approach, 2nd edn. London: Routledge.Â Wilson, A.G. 1972: Theoretical geography: some speculations. Transactions, Institution of British Geographers 57: 31-44.
Suggested Reading Bird (1975).Â Chouinard et al. (1984).Â Sayer (1992), ch. 8.