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
Human nature Human nature Human nature is a bundle of fundamental characteristics—including ways of thinking, feeling, and acting—which humans tend to have naturally. The questions of whether truly fixed characteristics exist, what these natural characteristics are, and what causes them, are among the oldest and most important questions in philosophy and science. The science that examines human nature is known as psychology and more recently also neuroscience. The concept of human nature is traditionally contrasted not only with unusual human characteristics, but also with characteristics which are derived from specific cultures, and upbringings. The "nature versus nurture" debate is a well-known modern