771. The man who indulges in the memory only, that is, in such studies as are of the memory, or in other things only for the sake of the memory, in the other life has very little understanding of what spiritual truth is, and still less what celestial. He remains fixed in his own particular ideas, which form a callosity, as it were, by which his brain is encompassed as with bone, or with a skull. This callosity must first be shaken off before the truth can penetrate, and before spiritual and celestial cognitions can have any place. Such callosity is dissipated with difficulty, and indeed with suffering, or if perchance in some other way it must become as though softened after a considerable lapse of time. This has been shown me by much experience, and just as often have I wondered at the representation of this callosity.