To dream is to imagine while sleeping.
The purpose of dreams is still little known. Dreaming is important, however, not only in medicine, but also in metaphysics, due to the arguments of the idealists. In dreaming we have an internal sentiment of ourselves and sometimes even a delirium great enough to see some things outside of ourselves. We ourselves act willingly or not, and finally all the objects of dreams can be seen to be figments of our imagination. The things that strike us most strongly during the day appear to our soul while in repose; this is common enough, even in animals. The cause of dreams is thus all impressions—strong, frequent and powerful—in any case.