29. The ongoing and widespread sighting of spirits is extremely rare, but isolated apparitions are quite frequent, especially at the time of death. The liberated spirit seems to be in a rush to see its relatives and friends again, as if to advise them that it has just left the earth and to tell them that it is still alive. Any person can delve into his or her memories and see how many authentic incidents of this type - unperceived at the time - have occurred not only at night during sleep, but in broad daylight while wide awake. Formerly, such incidents would have been considered supernatural and extraordinary, and attributed to magic and sorcery; today, disbelievers attribute them to imagination. However, since Spiritist science has provided the key to them, we know how they are produced and that they are not outside the order of natural phenomena.