Blind Commitment To A Theory Is Not

One May Rationally Stick To A Degenerating Research Programme Until It Is Overtaken By A Rival And Even After. What One Must Not Do Is To Deny Its Poor Public Record... It Is Perfectly Rational To Play A Risky Game: What Is Irrational Is To Deceive Oneself About The Risk.

No Experimental Result Can Ever Kill A Theory: Any Theory Can Be Saved From Counterinstances Either By Some Auxiliary Hypothesis Or By A Suitable Reinterpretation Of Its Terms.

In Degenerating Programmes, However, Theories Are Fabricated Only In Order To Accommodate Known Facts

The Classical Example Of A Successful Research Programme Is Newton's Gravitational Theory: Possibly The Most Successful Research Programme Ever.

There Is No Falsification Before The Emergence Of A Better Theory.