Naturalism (also called objectivism and positivism), is the worldview growing from modern natural science and technology that has been spreading from Northern Europe since the Renaissance. It is based on the basic concept that nature is real, and that there is nothing else. In other words, the concept of spirits, souls, and other outside forces is incorrect, and only what we can see and touch, or what is "real" is what actually exists. There are also other definitions for naturalism, but the previous explanation is the one that most people hold to and the one that makes the most general sense for believers. Nature, therefore, is a very closed system and which contains only natural causes and the effects of those causes. The position of those that believe in naturalism is a metaphysical one, and deals with the types of causal relationships exist. Part of the belief then becomes that everything in the world that happens has a cause that is natural. This belief is not held by the more mainstream and larger religions, as these religions often use God or some form thereof as the cause for many different events that are seen throughout the life of an individual. .

             When naturalism is examined in a more complex way, it can be seen that the definition of "natural" or "nature" is not the same for all people - even if all of those people believe in naturalism. For example, natural can mean everything that is in the world and can be seen, touched, etc., or natural can be that plus other things that cannot be seen. In other words, reality that exists outside of nature. There are also those that hold to the belief that not everything that exists is natural, and therefore there are non natural issues that must be addressed within the 'real world.' .

             As for whether naturalism has any sound basis in science is something that can be debated. Obviously, those that believe in naturalism feel that there is a basis to it or some reason that they feel it is a worthwhile theory.