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306 Karl Popper: Conjectures and Refutations

The scientific method relies on falsification rather than verification, and scientific theories are constantly subject to testing and potential refutation.



 "Conjectures and Refutations" explores the philosophy of science and the principles of critical rationalism. Karl Popper argues that science progresses through the formulation of conjectures, followed by rigorous attempts to refute them. He emphasizes the importance of falsifiability and critical analysis in scientific inquiry, challenging the notion that science seeks to prove theories true. With insightful examples and engaging prose, Popper advocates for an open society driven by critical thinking and rigorous testing of ideas.


Title: Conjectures and Refutations: The Growth of Scientific Knowledge

Author: Karl Popper

Publishing Year: 1963

Publisher: Routledge

Length in Hours: 22 hours 14 minutes

5 main ideas

  1. Falsification: Popper asserts that the criterion of demarcation between science and non-science lies in falsifiability, the potential for empirical testing and potential refutation of scientific theories.
  2. Growth of Scientific Knowledge: Scientific progress occurs through a process of conjectures and refutations, where theories are continually subjected to critical analysis and potential falsification.
  3. Fallibility of Science: Popper rejects the idea of absolute certainty in scientific theories and emphasizes that science can only provide provisional explanations, subject to future scrutiny and potential refutation.
  4. Open Society and Criticism: Popper advocates for an open society that encourages critical thinking, rigorous debate, and the continuous testing of ideas, fostering intellectual growth and progress.
  5. Science and Pseudoscience: Popper distinguishes between genuine scientific inquiry, which is characterized by falsifiability and self-critical analysis, and pseudoscience, which lacks these essential features.

5 funny quotes

  1. "You may tell the reader frankly that you are doing a little bit of spying on him." - Karl Popper
  2. "Philosophers should try to create the same sense of perplexity as is aroused by the naive but profound questions of children." - Karl Popper
  3. "We are all in the gutter, but some of us are looking at the stars." - Karl Popper (quoting Oscar Wilde)
  4. "Science may be described as the art of systematic over-simplification; the art of discerning what we may with advantage omit." - Karl Popper
  5. "I think that only bold conjectures and risky predictions deserve attention. It may be that only bold conjectures can be warranted." - Karl Popper

5 thought-provoking quotes​

  1. "Science may be described as the art of systematic over-simplification." - Karl Popper
  2. "Theories are nets cast to catch what we call 'the world': to rationalize, to explain, and to master it." - Karl Popper
  3. "The game of science is, in principle, without end. He who decides one day that scientific statements do not call for any further test, and that they can be regarded as finally verified, retires from the game." - Karl Popper
  4. "It is easy to obtain confirmations or verifications, for nearly every theory—if we look for confirmations." - Karl Popper
  5. "Our knowledge can only be finite, while our ignorance must necessarily be infinite." - Karl Popper

5 dilemmas

  1. The problem of induction: How can we justify the generalization from observed instances to unobserved instances, and how do we overcome the uncertainty inherent in induction?
  2. The demarcation problem: What criteria can be used to distinguish between scientific and non-scientific theories, and how do we differentiate between genuine scientific inquiry and pseudoscience?
  3. The underdetermination of theories by evidence: How do we decide between competing scientific theories that explain the same set of observations, especially when there may be multiple explanations?
  4. The challenge of theory choice: How do scientists decide which theories to pursue and test, and what factors influence the acceptance or rejection of certain theories?
  5. The problem of scientific progress: How can we determine whether a scientific theory is making genuine progress, and what constitutes progress in the field of science?

5 examples

  1. Newton's theory of gravity was subjected to rigorous testing and potential refutation through experiments conducted by other scientists, such as Henry Cavendish.
  2. Einstein's theory of relativity faced challenges and critical scrutiny from the scientific community, including Arthur Eddington's observations during the solar eclipse.
  3. The pharmaceutical company Pfizer conducted extensive clinical trials to test the efficacy and safety of their COVID-19 vaccine.
  4. Charles Darwin's theory of evolution faced criticism and counterarguments from religious figures, including Bishop Samuel Wilberforce during the Oxford evolution debate.
  5. The Large Hadron Collider (LHC) at CERN in Switzerland is an example of a scientific project that aims to test and validate fundamental theories in physics, such as the existence of the Higgs boson.

Referenced books

  1. "On the Origin of Species" by Charles Darwin
  2. "The Structure of Scientific Revolutions" by Thomas S. Kuhn
  3. "The Logic of Scientific Discovery" by Karl Popper
  4. "The Poverty of Historicism" by Karl Popper
  5. "Principia Mathematica" by Alfred North Whitehead and Bertrand Russell

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