It is when we begin to consider the premises that are necessary for arriving at the profound truths of the universe that we find the weakness of rationalism.

How are we going to be provided with premises for this end?
Shall we begin by saying "There is a God" or "There is no God"?
How is the pure reasoning faculty to decide upon the premises in the matter of the great Beyond?
We may weigh the arguments for and against a certain position, and we may think that the probability lies in a certain direction, but to decide finally and with certainty by mere cold logical reasoning is impossible.

We may bring out into prominence through logical reasoning truths that were previously only implicit, but to arrive at absolute truth with regard to the invisible world, through intellect alone, has long been admitted to be an impossibility.

The illusion of those who would believe that truth which was not already implied in the premises could ever be obtained by mere intellectual reasoning has long since been dispelled.
Perhaps it comes as a shock to the reader who has always insisted upon a clear intellectual understanding and a rigid reasoning upon all things, to find within what narrow limits, after all, the intellect itself has to work--it can do little more than make more or less certain generalisations concerning the world of experience, and then to argue from these, or from definitions that it itself has framed.

Of course some of the ancient philosophers did try through a course of rigid reasoning to solve the great problems, and for a long time it was customary to expect that all philosophers should proceed in the same way.
Modern philosophers, of whom William James, Bergson, and Eucken are conspicuous examples, have appreciated the futility of such a task, and have sought other means of solving the problem.