In our discussion thus far, we have been assuming the possibility of aesthetic theory. But what shall we say in answer to the mystic who tells us that beauty is indefinable? First of all, I think, we should remind him that his own thesis can be proved or refuted only through an attempt at a scientific investigation of beauty. Every attempt to master our experience through thought is an adventure; but the futility of adventures can be shown only by courageously entering into them. And, although the failure of previous efforts may lessen the probabilities of success in a new enterprise, it cannot prove that success is absolutely impossible. Through greater persistence and better methods the new may succeed where the old have failed. Moreover, although we are ready to grant that the pathway to our goal is full of pitfalls, marked by the wreckage of old theories, yet we claim that the skeptic or the mystic can know of their existence only by traveling over the pathway himself; for in the world of the inner life nothing can be known by hearsay. If, then, he would really know that the road to theoretical insight into beauty is impassable, let him travel with us and see; or, if not with us, alone by himself or with some one wiser than we as guide; let him compare fairly and sympathetically the results of theoretical analysis and construction with the data of his firsthand experience and observe whether the one is or is not adequate to the other. Again, the cleft between thought and feeling, even subtle and fleeting aesthetic feeling, is not so great as the mystics suppose. For, after all, there is a recognizable identity and permanence even in these feelings; we should never call them by a common name or greet them as the same despite their shiftings from moment to moment if this were not true. Although whatever is unique in each individual experience of beauty, its distinctive flavor or nuance, cannot be adequately rendered in thought, but can only be felt; yet whatever each new experience has in common with the old, whatever is universal in all aesthetic experiences, can be formulated. The relations of beauty, too, its place in the whole of life, can be discovered by thought alone; for only by thought can we hold on to the various things whose relations we are seeking to establish; without thought our experience falls asunder into separate bits and never attains to unity. Finally, the mystics forget that the life of thought and the life of feeling have a common root; they are both parts of the one life of the mind and so cannot be foreign to each other.