David Cameron: Conservatism is about seeking the common ground

The brilliance of Keith Joseph was that he applied his great mind to the most important and pressing problems that faced Britain in the 1970s: persistently high inflation, rising unemployment, irresponsible trade unionism and the growing threat of absolute economic decline.

But the Conservative Party chose to live off his legacy for too long. Put simply, after the success of the Thatcher governments, we gave the appearance of having stopped thinking like Conservatives.

Since 1997, the Conservative Party has been looking to find its true voice. There are three responses to electoral defeat. The first is to retrench - to concentrate on the core, on ideological purity. The second is to surrender,to junk your own principles and run after those of the other side. The third response is to seek Keith Joseph's common ground - distinct from your opponents, distinct from the stereotype of your own position, but in tune with the aspirations of the people and with your own true values.

Of course, this is the hardest of the three options. It takes time to bring to fruition. It is not glamorous. It does not involve the symbolic ditching of totemic clauses. These are the three choices which Pitt the Younger faced in the late 18th century. Which Peel, and after him Disraeli, faced in the 19th. Which Baldwin faced in the 1930s and Churchill in the 1950s. And they are the choices which Margaret Thatcher faced in the 1970s and 80s.

All these leaders heard siren voices calling for retrenchment or for surrender. But the reason the Conservative Party is alive today is because these great leaders chose the third of these three options. They chose the common ground. Not socialism. Not liberalism. But Conservatism, authentic - yet appropriate to the time.