The significance of critical realism in 19th century

General philosophy
Critical realism is presently most commonly associated with the work of Roy Bhaskar.Bhaskar developed a general philosophy of science that he described as transcendental realism,and a special philosophy of the human sciences that he called critical naturalism.The two terms were elided by other authors to form the umbrella term critical realism.
Transcendental realism attempts to establish that in order for scientific investigation to take place,the object of that investigation must have real,manipulable,internal mechanisms that can be actualised to produce particular outcomes.This is what we do when we conduct experiments.This stands in contrast to empiricist scientists' claim that all scientists can do is observe the relationship between cause and effect.Whilst empiricism,and positivism more generally,locate causal relationships at the level of events,Critical Realism locates them at the level of the generative mechanism,arguing that causal relationships are irreducible to empirical constant conjunctions of David Hume's doctrine; in other words,a constant conjunctive relationship between events is neither sufficient nor even necessary to establish a causal relationship.
The implication of this is that science should be understood as an ongoing process in which scientists improve the concepts they use to understand the mechanisms that they study.It should not,in contrast to the claim of empiricists,be about the identification of a coincidence between a postulated independent variable and dependent variable.Positivism/falsification are also rejected due to the observation that it is highly plausible that a mechanism will exist but either a) go unactivated,b) be activated,but not perceived,or c) be activated,but counteracted by other mechanisms,which results in it having unpredictable effects.Thus,non-realisation of a posited mechanism cannot (in contrast to the claim of positivists) be taken to signify its non-existence.
Critical naturalism argues that the transcendental realist model of science is equally applicable to both the physical and the human worlds.However,when we study the human world we are studying something fundamentally different from the physical world and must therefore adapt our strategy to studying it.Critical naturalism therefore prescribes social scientific method which seeks to identify the mechanisms producing social events,but with a recognition that these are in a much greater state of flux than they are in the physical world (as human structures change much more readily than those of,say,a leaf).In particular,we must understand that human agency is made possible by social structures that themselves require the reproduction of certain actions/pre-conditions.Further,the individuals that inhabit these social structures are capable of consciously reflecting upon,and changing,the actions that produce them鈥攁 practice that is in part facilitated by social scientific research.
[edit] Developments
Since Bhaskar made the first big steps in popularising the theory of critical realism in the 1970s,it has become one of the major strands of social scientific method - rivalling positivism/empiricism,and post-structuralism/relativism/interpretivism.
An edited volume,Critical Realism:Essential Readings,is currently the most appreciated and available reader in critical realism.
There is also a Journal of Critical Realism,which publishes articles on the theory and results of the practice of critical realist social science.See also,Journal for the Theory of Social Behaviour,published by Blackwell,which also publishes theoretical and empirical realist social science.
A lively email discussion on critical realism can be joined on the critical realism e-mail list.
Since his development of critical realism,Bhaskar has gone on to develop a philosophical system he calls dialectical critical realism,which is most clearly outlined in his weighty book,Dialectic:the pulse of freedom.
Bhaskar is frequently criticised for the density and obscurity of his writing.That said,some readers may actually appreciate his meticulous linguistic precision,which can be time consuming to read,but read properly,it is possible to understand the precise and unambiguous meaning behind his writing.An accessible introduction was written by Andrew Collier.Andrew Sayer has written accessible texts on critical realism in social science.Danermark et al.have also produced an accessible account.Margaret Archer is associated with this school,as is the ecosocialist writer Peter Dickens.
David Graeber relies on critical realism,which he understands as a form of 'heraclitean' philosophy,emphasizing flux and change over stable essences,in his anthropological book on the concept of value,Toward an anthropological theory of value:the false coin of our own dreams.
Robert Willmott has developed the realist ("morphogenetic") social theory of Margaret Archer in his Education Policy and Realist Social Theory:primary teachers,child-centred philosophy and the new managerialism,published by Routledge.