The experiences of the philosophers are bound to be different, because no two human beings can have exposure to the same historical, political, cultural, and economic circumstances. They may possess contrasting information on the same subject, or they may use contrasting methodologies to study their information. The philosophy that they develop will carry the influence of their experiences and the philosophical methods that they use.
I am not advocating relativism—I am not saying that philosophical conclusions have to be dependent on the personal inclinations of the philosophers. But it is true that a rational philosopher can philosophize on the big questions only on the basis of the experience and information that is available to him. Therefore, it is difficult, if not impossible, to find two rational and independent minded philosophers who agree on every issue.
The differences among the philosophers are not bad for philosophy. Through their arguments and counter-arguments, the philosophers are often able to identify the problems in their thought and if they manage to resolve these problems their philosophy becomes more consistent and complete.
A philosophy thrives when the intellectuals are talking about it. It doesn’t matter if they are arguing against the philosophy; as long as they are arguing about it, they are ensuring that it remains relevant. Even if a philosophy is refuted, it can remain relevant as long as the intellectuals don’t abandon it. There are several examples in history of refuted philosophies growing from strength to strength and acquiring great social power.
To propagate his philosophy, a philosopher must to get other philosophers to talk about it. He must welcome philosophical differences—because a philosophy thrives when there is controversy about it. The bigger the controversy, the better it is. A philosophy can survive (it can even thrive) after being decisively refuted, but if it is ignored, it is dead.