Week 2 chapter 3 “Popper’s Critical Rationalism”
Popper’s demarcation of science from non-science rested on the notion of falsifiability. Science
distinguishes itself from pseudo-science by being able to be falsified. In this way the theory was risky
and allowed for critique. It was a way of admitting that human knowledge was not yet able to
encompass real scientific knowledge. Pseudo-science on the other hand was immune to critique by
writing theories so general as possible. This is called the immunizing stratagem. For popper pseudo-
science was not necessarily useless, it would still have meaning and could be falsified in a later point
in time. Popper’s view thus clashed with the traditional logical positivists view.
Popper accepted the induction problem and had the opinion that real science never really used the
induction method. The induction method was prone to logical asymmetry no universal statement
can be verified by a collection of singular statements but one singular statement can contradict a
universal statement. Instead he used the falsifiability notion, on the grounds that real science should
not be easy and there always exisists some evidence that can falsify the claim. He held that a
scientific rule is conclusively falisifiable but not conclusively verifiable. As one exception refutes the
claim and one can never no if all possible observations are made. His theory of demarcation can be
stated as: observations from a sample can be divided into two categories the class of all those basic
statements with which it is inconsistent (the potential falsifiers of the theory) and secondly the class
of statements which it does not contradict. Both must be non-empty to make sure the theory is really
scientific. Because every scientific theory excludes some observations it cannot possibly be verified.
Therefor a theory can be rigorously tested, and held as the best theory at that moment, until is
bettered by another theory.
For Popper, the growth of knowledge depends on problems and our attempts to solve them. Solving
theories consists of formulating theories in which problems can be solved. This was, according to
popper dependent on the capability of creative imagination. Along these lines, he advocated
deductive testing where conclusions are inferred through hypothesis conjured by imagination. These
conclusions are then compared and tested if they corroborate or falsify the hypothesis. This boils
down to whether one theory has better predictive power than the other, due to its better empirical
content. Popper holds the logical empiricists view that one can deduce meaning from experience but
does not place too much meaning on experience. He rather uses experiences as a method to show
which theories are false rather than which are true. A theory can be said to corroborate by past
experience with a statement if it withstands the best other comparable predictions from other
theories. i.e. it holds the best predictive power.
For Popper critical spirit is the essence of science.
Popper rejected the approach to science of picking the most probable explanation. He placed more
value on the predictability, which is dependent on the empirical content which is higher the more
improbable it is as it has more potential falsifiers. This does increase the testability of a theory.
Unsurprisingly Popper was uneasy with the notion of truth, every theory must remain an open ended
hypothesis and potentially be false.
Popper and Friedman agree on these grounds, that predictability is the most important justifier of
theories above probability.
Propper opposed historicism the view that history develops according to certain principles. Primarily
using historic events to making predictions towards a deterministic end. He argued that what
happens is largely the unplanned and unforeseeable result of the actions of many individuals. As
Popper’s demarcation of science from non-science rested on the notion of falsifiability. Science
distinguishes itself from pseudo-science by being able to be falsified. In this way the theory was risky
and allowed for critique. It was a way of admitting that human knowledge was not yet able to
encompass real scientific knowledge. Pseudo-science on the other hand was immune to critique by
writing theories so general as possible. This is called the immunizing stratagem. For popper pseudo-
science was not necessarily useless, it would still have meaning and could be falsified in a later point
in time. Popper’s view thus clashed with the traditional logical positivists view.
Popper accepted the induction problem and had the opinion that real science never really used the
induction method. The induction method was prone to logical asymmetry no universal statement
can be verified by a collection of singular statements but one singular statement can contradict a
universal statement. Instead he used the falsifiability notion, on the grounds that real science should
not be easy and there always exisists some evidence that can falsify the claim. He held that a
scientific rule is conclusively falisifiable but not conclusively verifiable. As one exception refutes the
claim and one can never no if all possible observations are made. His theory of demarcation can be
stated as: observations from a sample can be divided into two categories the class of all those basic
statements with which it is inconsistent (the potential falsifiers of the theory) and secondly the class
of statements which it does not contradict. Both must be non-empty to make sure the theory is really
scientific. Because every scientific theory excludes some observations it cannot possibly be verified.
Therefor a theory can be rigorously tested, and held as the best theory at that moment, until is
bettered by another theory.
For Popper, the growth of knowledge depends on problems and our attempts to solve them. Solving
theories consists of formulating theories in which problems can be solved. This was, according to
popper dependent on the capability of creative imagination. Along these lines, he advocated
deductive testing where conclusions are inferred through hypothesis conjured by imagination. These
conclusions are then compared and tested if they corroborate or falsify the hypothesis. This boils
down to whether one theory has better predictive power than the other, due to its better empirical
content. Popper holds the logical empiricists view that one can deduce meaning from experience but
does not place too much meaning on experience. He rather uses experiences as a method to show
which theories are false rather than which are true. A theory can be said to corroborate by past
experience with a statement if it withstands the best other comparable predictions from other
theories. i.e. it holds the best predictive power.
For Popper critical spirit is the essence of science.
Popper rejected the approach to science of picking the most probable explanation. He placed more
value on the predictability, which is dependent on the empirical content which is higher the more
improbable it is as it has more potential falsifiers. This does increase the testability of a theory.
Unsurprisingly Popper was uneasy with the notion of truth, every theory must remain an open ended
hypothesis and potentially be false.
Popper and Friedman agree on these grounds, that predictability is the most important justifier of
theories above probability.
Propper opposed historicism the view that history develops according to certain principles. Primarily
using historic events to making predictions towards a deterministic end. He argued that what
happens is largely the unplanned and unforeseeable result of the actions of many individuals. As
