Volcano of classifying magmatic volcanoes is by their frequency of eruption, with those that erupt regularly called active, those that have erupted in historical times but are now quiet called dormant or inactive, and those that have not erupted in historical times called extinct. However, these popular classifications—extinct in particular—are practically meaningless to scientists. They use classifications which refer to a particular volcano's formative and eruptive processes and resulting shapes. There is no consensus among volcanologists on how to define an "active" volcano. The lifespan of a volcano can vary from months to several million years, making such a distinction sometimes
Buddha-nature this lifetime through chanting the name of the Dharma of the Lotus Sutra: "[T]the Buddha nature within us is summoned forth and manifested by our chanting of Nam-myoho-renge-kyo." The potential for Buddhahood exists in the whole spectrum of the Ten Worlds of life, and this means that all people, including evil doers, have Buddha nature, which remains as a dormant possibility or a theoretical potential in the field of emptiness or non-substantiality until it is materialized in reality through Buddhist practice. In his letter "Opening the Eyes of Wooden and painted Images" Nichiren explains that insentient matter (such as trees,