Towards a Liberal Education
Popper's Revolutionary Theory of Knowledge

Printed in Honi Soit at the University of Sydney in 1971

Preface 2010

Popper’s Conjectural, Objectivist, Social, and Metaphysical Turns

Since this essay was first written it has become apparent that the reception of Popper’s ideas has been limited by widespread misconceptions that readers bring with them to the texts. This applies especially to people with a background in philosophy. It is widely accepted that Popper was a kind of eccentric positivist who simply substituted falsification for verification, and distorted versions of his ideas are circulated with the label “falsificationism” attached. Quite likely one of the most influential books in this regard is What is this thing called science? and I trust that this review of that otherwise admirable text will clarify the situation.

The standard account of Popper as a falsificationist does not do justice to the full extent of  Popper’s program, starting with the first step which can be described as a full-blooded “conjectural turn”, to claim that even our best theories may be rendered problematic by new evidence, new criticisms and new theories. This anticipated the “hermeneutic turn” when appreciation of the theory-dependence of observations and arguments became more widespread in the wake of Kuhn and the modern French theorists. Other “turns” include the “objectivist turn” to break with the obsession with the justification of beliefs and instead to focus on the strengths and weaknesses of  theories that are stated in a public, inter-subjective or “objective” form. Then there is Popper’s “social turn” to examine the function of institutions, traditions, conventions and “rules of the game” in science and society. And finally the “metaphysical turn” to recognise the pervasive influence of  philosophical or metaphysical ideas which are the framework assumptions or presuppositions of  thought.

For more on these turns.

And now, back to...

Towards a Liberal Education

Young radicals all over the world are calling out for the reorganisation of society and particularly of the education system. As strange as it may seem, the most powerful weapons at their disposal have been forged by Sir Karl Popper, who is a liberal and a humanist, certainly not a Marxist revolutionary. He is written off as a reactionary by the New Left but he has fought as hard as anyone for the open society and the rights of the individual. He has also pointed out that to protect freedom and improve the human condition we need advances in sociology so that we can hope to obtain the desired results from social reforms and political experiments.

He is opposed to tyranny and he is also opposed to irrationalism, which may alienate him from those who reject reason. Our social problems persist despite the triumph of science (which is the epitome of reason), and so, the argument runs, what is the use of science and reason?





Scientific knowledge is capable of growing by the detection and correction or error, though its growth can never be completed. It does not grow in a disciplined, orderly or predictable way, but rather by unjustified leaps of imagination, controlled by the use of logic, critical analysis and experimental tests.

Our knowledge in a given field does not consist of a mass of facts or a set of verified laws, it consists of a body of hypotheses along with an account of the tests and other arguments that have been used in attempts to refute them. There is no opposition between imagination and reason because they have different (and complementary) roles to play. There is no antagonism between theorising and fact finding provided that we have a clearly formulated problem in mind when we start looking for facts.

This theory of knowledge has some political implications. The positivist-empiricist-inductivist may have thought that he did not need to actively make decisions about his subject matter. The task of the scientist was to collect and collate information to steadily record the tale told by the book of nature. However, this idea of the passive observer-collector cannot be sustained. If the scientist wants to advance the frontier of knowledge, even to the smallest degree that the average honours student should aspire to achieve, he has to make an effort and bring into action both the imagination and the critical faculties. There is also the consideration that the findings are quite likely to be used and the scientist (or at least the community of scientists) is morally responsible for warning of potential dangers and monitoring any dubious applications.

Scientists can only approach the truth by conjectures and by critical tests, and if they accept their social responsibilities they will carry their critical attitude out of the laboratory, to participate, like everyone else, in a continuous process of non-violent cultural revolution.

Note: People who wish to explore Popper's views on education will find a compilation of his scattered comments here. hese are grouped under three heads: moral education, the role of public education and education in science. A comment on the deficiences of liberal education in its traditional form can be found here (note 9 to Chapter 11 OSE).

Writings on Karl Popper

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