In our view, loss of Tonal is an important cause of illness. The Tonal may be and commonly is lost under normal conditions; during sleep and other times of unconsciousness, and during sexual congress (the participants' Tonallis are usually off having sex themselves at such times). Loss of Tonal for long periods can be serious, and produces conditions your doctors refer to as "anxiety," "depression," and "panic attacks." Permanent loss of Tonal is fatal. In some other cultures this aspect of the Tonal may be called the "Shadow" or the "Doppelganger," loss of which is a serious matter. It is said to be possible to encounter a wandering Tonal, it simply isn't seen as unusual - a person's Tonal looks just like that person.