and sincere men, implies that they are pursuing a will-o’-the-wisp. But as soon as the true function of rationalism is understood, that it is a gradual approach to ideas of clarity and generality, the discord is what may be expected.
The various cosmologies have in various degrees failed to achieve the generality and the clarity at which they aim. They are inadequate, vague, and push special notions beyond the proper limits of their application. For example, Descartes is obviously right, in some sense or other, when he says that we have bodies and that we have minds, and that they can be studied in some disconnection. It is what we do daily in practical life. This philosophy makes a large generalization which obviously has some important validity. But if you turn it into a final cosmology, errors will creep in. The same is true of other schools of philosophy. They all say something which is importantly true. Some types of philosophy have produced more penetrating cosmologies than other schools. At certain epochs a cosmology may be produced which includes its predecessors and assigns to them their scope of validity. But at length, that cosmology will be found out. Rivals will appear correcting it, and perhaps failing to include some of its general truths.
In this way mankind stumbles on in its task of understanding the world.
In conclusion we must recur to our initial question, which is the title of this discussion, The Function of Reason. If we survey the world as a physical
