Kuhn 1

Kuhn’s criticisms of Popper:

1) It is better to look at the actual history of science than to try to jam science into a preconceived logical framework.

2) Falsificationism only addresses a tiny portion of the history of science. Most scientists, most of the time, are not trying to falsify theories.

3) Theory change is not rational in the way that Popper describes it. A single falsifying instance would be treated as an anomaly (see below).

Kuhn has a historical perspective on the philosophy of science:

1) Normal Science:

a. Scientists work within a single paradigm.

b. Paradigm: a set of theories, questions, techniques, a general scientific ‘world view’ that all of the researcher agree on.

i. A paradigm is like a puzzle that everyone agrees on. Most of the time scientists are trying to fit pieces into the puzel, not trying to create a new picture.

ii. The geocentric universe is an example of a paradigm.

iii. Most scientists were trying to work out the details of how the sun and stars went around the earth.

c. Anomalies begin to accumulate.

i. An anomaly is an observation that conflicts with the current paradigm.

ii. According to Popper an anomaly ought to falsify a theory.

iii. Kuhn points out that most anomalies get ‘swept under the rug’.

1. When Galileo developed a telescope that allowed people to see the moons of Jupiter, most folks thought that the instrument was faulty.

iv. Eventually lots of anomalies accumulate and we get a scientific revolution.

2) Scientific revolution

a. There is a shift from one paradigm to another (paradigm shift).

i. It is like a gesalt shift (bunny/duck)

b. For example the change from a geocentric to a heliocentric view of the solar system.

3) New period of normal science.

a. There is a new paradigm, which is like a new puzzle.

b. For example, now scientists are trying to show how the sun is the center of the solar system instead of trying to show that the earth is the center of the solar system.

Incommensurability

For Popper Truth is relative to the world (correspondence theory of justification of true belief).

But for Kuhn, Truth is relative to the paradigm (coherence theory of justification of true belief).

Truth/facts/observations of one paradigm are incommensurable with the truth/facts/observations of a different paradigm.

• For Kuhn, what counts as true in one paradigm is different from what counts as true in a different paradigm.
• Another way of putting this is that truth does not survive a scientific revolution.
• If it did, it would be like a piece of one puzzle fitting into a different picture à it doesn’t happen and we get very frustrated when we try to make this work.