Transparancies for the lectures:

Importance of Prediction

C Important for everyday life

avoid danger : fire, global warming
obtain benefits : stock market

C Important in development of science

confirmed predictions increase confidence
e.g. general relativity
false predictions à rejection / modification
e.g. Larmarckianism (members of a species become better adapted over time as they inherit acquired features)

2 Projects : Description & Justification

Descriptive (is) vs. normative (ought)

- should distinguish between them as far as possible

Q1 : How do scientists make predictions? What methods do they actually use to make predictions?

Q2 : How should they make predictions? Which method (methods) of prediction is the best one? Can we show that these methods are rational?

Illustrates typical role of philosophy of science

Some features of predictions

Predictions are based on past experience

We think that certain things have been true in the past, e.g. theories, laws,

‚ We assume they are also true in the future, unless there is some reason to think otherwise.

Principle of Induction

If (a) something has always been true, and (b) we have no evidence suggesting that it will not be true, then, it will continue to be true in the future.

Descriptive claim : Principle of induction is presupposed in most predictions.

Normative question : why is it rational to use this principle in making predictions?

F The principle is not a necessary truth.

F No reason why something that was alway

F Why use the principle instead of guessing?

Because induction is more successful

Which is true. Better than guessing.
But why would this show that the principle is reasonable?
Is it because it shows that the principle will be more successful in the future?
But this prediction relies on the principle itself.

F Why use the principle instead of guessing?

Because induction is more successful

Which is true. Better than guessing.
But why would this show that the principle is reasonable?
Is it because it shows that the principle will be more successful in the future?
But this prediction relies on the principle itself.

s true will continue to be true. (Russell's chicken)

F Why use the principle instead of guessing?

Because induction is more successful

Which is true. Better than guessing.
But why would this show that the principle is reasonable?
Is it because it shows that the principle will be more successful in the future?
But this prediction relies on the principle itself.