Postpositivism

Fallibility and Warrants

Positivists sought to ground science in an incorrigible (uncorrectable) source of knowledge (e.g., sense data and logical truths). They held that there was a duty to build up the knowledge base on a [Page 1276]foundation of self-justifying beliefs. They also believed scientists should never go beyond observable phenomena. However, not even the best-entrenched claims in the natural sciences were found to fully meet these conditions. For example, physicists invoke atoms in their theories even though such entities must be inferred from observable phenomena. The content of most theories in science (except perhaps in pure mathematics) would thus need to be substantially altered to conform to strict positivist standards.

Postpositivists, in contrast, champion fallible knowledge (i.e., warranted truth claims can originate from a purely fallible source). For example, people seem to know what they ate for breakfast even though they have faulty memories. A passable epistemology of science as actually practiced, including education research, needs to recognize that scientists rely on fallible sources of information. Natural and social science have historically flourished despite the repeated failure of philosophers to ground it in only incorrigible truths.

Postpositivists further claim that knowledge can be objective without the need for absolute certainty. Objective knowledge has two senses: In the strong sense, it implies that humans can know about objects that exist independently of individual or social conceptions of reality. Such objective knowledge thus contrasts with subjective knowledge, which is limited to the content of one’s own mind (e.g., whether vanilla ice cream tastes good). In the weak sense, objective knowledge is based on intersubjective agreement, in which agents who engage in competent inquiry should converge in their beliefs. Such inquiry can yield warranted assertions. In this weaker sense, “objective” contrasts with being biased rather than subjective. Bias (e.g., racism, sexism, and classism) is a tendency to arrive at conclusions that support a vested interest, regardless of what the obtained evidence suggests. Scientists always embody a subjective outlook, but they need not be biased.

Postpositivists disagree about whether science can recover strong objective knowledge. However, they typically agree that there are objective criteria for deciding what constitutes a warranted truth claim. They also concur that science comes from a fallible source. To reconcile the concepts of fallibility and warrant in a single position, postpositivists turn to one of three approaches: evolutionary epistemology, realism, and pragmatism.

Evolutionary Epistemology

Karl Popper (1902–1994) provides a vivid example of an evolutionary epistemologist. He likened theory selection in science to natural selection. In the Darwinian model, natural selection adapts species to environments without foresight. Some random mutations confer advantages. Animals lucky enough to inherent these survive longer than their evolutionary competitors, and thus, they have more offspring. This process naturally adapts species to their environments.

...