1421. Consequently they were like flames, running through and delighting in the subtle things [of my memory], thus those things which I had seen in the heavens, which they said that they knew. I then said to them that perhaps they only supposed that they knew them, and nevertheless did not know them, because a spirit supposes that he himself knows and had known the things which he perceives in man from his memory. I perceived, moreover, that in the plane of the occiput at the back, a little to the left, there was a multitude of these spirits who together perceived this, and that they could have such thought because they attend only to the reality and thus to the interiors, being unwilling to tarry in externals; for such is the memory with spirits.