The idea that all things can be explained by natural laws is as ancient as philosophy itself. Naturalism and Supernaturalism comprise a divide between the two most fundamental ways of looking at reality. If you don’t believe in Gods or an immaterial soul, then you are a naturalist. There are areas where the lines are blurred, and non-theists may hold on to specific non-naturalistic beliefs, but in general the division between the two ways of looking at reality holds good. The practice of rejecting supernatural claims was found among the Carvaka of ancient India and the materialist philosophers of ancient Greece. This tradition has continued down to the present day and has been analyzed and codified into different forms. The one that is the simplest to understand is the philosophical definition of naturalism. So let’s begin with this.
Philosophical Naturalism is the idea that nature is all there is. Also known as metaphysical naturalism, it is an outright rejection of all supernatural. Even in the presence of a seemingly supernatural situation, metaphysical naturalism will claim that there is a natural explanation underlying it. All human knowledge comes from such a naturalistic understanding. When philosophical naturalism is compromised, knowledge hits a wall.
A good example is Newton and the problem of planetary orbits. After spectacular work in the Principia Mathematica, describing previously undiscovered forces in the universe and a good many laws of physics than were known at that time, Newton reached an impasse. His model of the solar system could not explain why the planets did not spiral down into the sun. After asking naturalistic questions and answering them, providing humanity with some of the greatest inspirations in science, Newton finally proposed a supernaturalistic ‘explanation’. He theorized that God must intervene with the motion of the planets to set things right (notice that this is not really an explanation; saying “God did it” is like saying it happens by magic). Newton, after all that brilliant thinking, could not solve the problem because he evoked the nonexistent supernatural. A 100 years later, Laplace famously solved the problem by asking only naturalistic questions. Read more about this here.
A less dogmatic position is Scientific Naturalism, also known as Methodological Naturalism. Methodological naturalism posits that the naturalistic method is the only way for us humans to understand the universe. By definition, it concedes that there might exist non-naturalistic entities but the tools that we as humans possess can only identify natural entities. This is an epistemological claim (a claim about the nature and acquisition of knowledge). The scientific method as a refined systematic process is the culmination of a long history of honing the tools that we possess in order to understand reality. It is based on the philosophy of naturalism. Scientific Naturalism requires that hypothesis be formed and tested under the assumption that there are natural causes for all phenomena.
The modern Naturalism Movement is a socio-political movement that is rooted in naturalist philosophy. It is a relatively modern movement in it’s present-day form. The premier organization that promotes naturalism as a comprehensive world-view is the Center for Naturalism. Tom Clark, who has written here on Nirmukta, is the director of the CFN. His book Encountering Naturalism: A Worldview and Its Uses presents arguments for the naturalistic worldview and it’s implications. Many in the naturalism movement have taken it upon themselves to question non-natural claims that are believed without question by many people including some skeptics. Chief among these is the belief in contra-causal free-will (which is the belief in a human agency devoid of natural causes and beyond the control of the self- it evokes a dualistic notion of mental function and assigns a supernatural exception to the causal rule of nature). Tom Clark calls this the ‘Little God‘, one that even many atheists do not doubt. The CFN ponders on the implications of a lack of free-will on society and many in the movement hold that a social order without the non-natural idea of free-will must be a more compassionate and just society.
Religious Naturalism is a fast-growing movement within the free-thought community. It is essentially scientific naturalism coming together with religious language. This movement, which boasts Ursula Goodenough as one of it’s intellectual heavyweights, includes the diverse community of Pantheists. Religious Naturalism is based on the knowledge that, for the majority of human history, social rules and practices have been reinforced by religion. Despite the great suffering caused by the organized religions, some social aspects of religion have usually performed some required role in society. Religious naturalists believe that to replace supernatural religion we must adopt some practices and language from the world’s religions and incorporate naturalistic ideas about reality into them. Foremost among the qualities of religion that Religious Naturalists try to induce naturalism into are social cohesion and a mystical and metaphorical awe for nature. Some would call Carl Sagan a religious naturalist. I have written more about religious naturalism here.
Finally, Cultural Naturalism is the process of reconciling facts about the natural world with social and emotional states that shape human behavior. The facts about the natural world are best revealed to us through science. In essence, cultural naturalism attempts to reconcile scientific facts with human emotions, by placing the naturalistic facts in the context of human social life.
Non-natural concepts are of two types- Objective Supernatural Claims (OSCs) and Experiential Facts (EFs) (Note: Experiential Facts are ideas that are emotionally and consciously experienced by people). As long as a non-natural concept does not trespass on the domain of science (the natural world), it is an experiential fact (EF). Experiential facts do not make objective claims about reality, because they comprise of emotional brain states. These are acceptable beliefs under cultural naturalism (for example, ‘love’). Some other non-natural concepts make objective claims about the nature of reality. These are not experiential facts but objective supernatural claims (OSCs), and are not acceptable under cultural naturalism. Cultural Naturalism explores common culturally transmitted ideas using the criteria described above.
In intelligent animals, emotions have evolved as a control mechanism for voluntary brain function. Our emotional states are EFs. Our brains interpret the external and internal data in many ways. The trick is to adopt necessary EFs that do not compromise objective truth and reject the EFs that do. Humanity has struggled with this problem for millennia. Strictly speaking, scientific naturalism is not concerned with the EFs that permeate human culture. This must be the domain of a philosophy that goes beyond science itself. This is where cultural naturalism comes in.
For example, love is an experiential fact (EF). The underlying material causes of love are explained scientifically, but love itself does not exist outside the observer- that is, love is subjective. The philosophy of cultural naturalism reconciles the human emotion of love with the objective reality in which the idea of love ceases to exist. This is conditional upon the definition of love not making any objective supernatural claims (OSCs). ”God’ is a supernatural concept that does make objective truth claims about the natural world outside of the observer. Thus, it is not acceptable as an EF and is rejected under Cultural Naturalism. All moral values are EFs as long as they do not make any OSCs. The ideal of contra-causal free will is not an acceptable EF because it makes truth claims about reality. ‘God’ and ‘Free-will’ are OSCs.
Cultural Naturalism, therefore, is an amalgam of scientific naturalism and all the sociopolitical forms of naturalism. It’s influence is targeted on the culture that alters and is altered by human behavior. It’s purpose is very much like that of Religious Naturalism (to replace religions with a more positive and meaningful naturalistic philosophy than just atheism or skepticism). However, in addition to usurping language to augment natural facts and provide an alternative to the social benefits offered by primitive religions, cultural naturalism targets every area of human endeavor, including political and socio-economic conversations. It is the most general life-philosophy of those that endorse a naturalistic understanding of reality. In essence, Cultural Naturalism is the point where naturalistic philosophy meets human social living.