philosophical and metaphysical explanations with regard to the study of the universe. Both science and religion are not monolithic, timeless, or static because both are complex social and cultural endeavors that have changed through time across languages and cultures. The concepts of science and religion are a recent invention: the term religion emerged in the 17th century in the midst of colonization and globalization and the Protestant Reformation. The term science emerged in the 19th century out of natural philosophy in the midst of attempts to narrowly define those who studied nature (natural science), and the phrase religion and science emerged in the 19th century due to the reification of both concepts. It was in the 19th century that the terms Buddhism, Hinduism, Taoism, and Confucianism first emerged. In the ancient and medieval world, the etymological Latin roots of both science (scientia) and religion (religio) were understood as inner qualities of the individual or virtues, never as doctrines, practices, or actual sources of knowledge. In general the scientific method gains knowledge by testing hypotheses to develop theories through elucidation of facts or evaluation by experiments and thus only answers cosmological questions about the universe that can be observed and measured. It develops theories of the world which best fit physically observed evidence. All scientific knowledge is subject to later refinement, or even rejection, in the face of additional evidence. Scientific theories that have an overwhelming preponderance of favorable evidence are often treated as de facto verities in general parlance, such as the theories of general relativity and natural selection to explain respectively the mechanisms of gravity and evolution. Religion does not have a method per se partly because religions emerge through time from diverse cultures and it is an attempt to find meaning in the world, and to explain humanity's place in it and relationship to it and to any posited entities. In terms of Christian theology and ultimate truths, people rely on reason, experience, scripture, and tradition to test and gauge what they experience and what they should believe. Furthermore, religious models, understanding, and metaphors are also revisable, as are scientific models. Regarding religion and science, Albert Einstein states (1940): "For science can only ascertain what is, but not what should be, and outside of its domain value judgments of all kinds remain necessary. Religion, on the other hand, deals only with evaluations of human thought and action; it