Naturalism and natural sciences
Relationship to science
The naturalist perspective leads to accord philosophy to the data of the natural sciences. This agreement implies three types of requirements for the philosophy:
- Scientific data must be integrated into philosophical reflection;
- Philosophical theses must be compatible with these data;
- The philosophical questioning must be formulated in such a way that it can receive an answer from the natural sciences.
Daniel Dennett sums up these requirements in his definition of naturalism, a position he himself defends:
“My fundamental perspective is naturalism, the idea that philosophical investigations are not superior to, or prior to, investigations in the natural sciences, but in partnership with those truthseeking enterprises, and that the proper job for philosophers here is to clarify and unify the often
warring perspectives into a single vision of the universe.”
Naturalism is sometimes considered by those who support it as a tacit “metaphysical assumption” of science, or as an “ontological and philosophical postulate” on which it bases its development. This thesis is notably supported by Martin Mahner who distinguishes two possible interpretations of the relationship to the sciences of what he indifferently calls “metaphysical or ontological naturalism”: In the weak sense, ontological naturalism is simply a part of the metaphysical postulates underlying contemporary science as a result of historical contingencies; so that ontological naturalism could be replaced by its antithesis at any time and science would continue to function well. In the strongest sense, ontological naturalism is essential to science; that is to say, if we removed it from the metaphysics of science, what we would obtain would no longer be science.
He considers that the strong sense is to be privileged, because the future and the success of science are linked according to him to the ontological theses of naturalism.
In theory, naturalism grants physics a privileged position among the sciences. More exactly, he considers that properly physical explanations are those which best meet the scientific requirements of explanations by causes and laws. Because the causes and the physical laws would govern fundamentally all the phenomena, the physical explanations which are based on them would be the only ones which can claim universality.
From the naturalistic perspective, physicalist reductionism (or physicalism) happens to be the best ontological position we have found to date, better for example than idealism, vitalism or dualism.
This ontological commitment to physics starts from the idea that fundamental and universal physical theories are distinguished from theories of the special sciences. The latter are said to be special, and not universal, because each of them concerns a domain of being limited, and because they depend on the theories of fundamental physics. They cannot, in fact, describe and explain the objects of their domain completely, by their own concepts, because they are obliged to have recourse to concepts and laws of fundamental physics. Biology, for example, is a special case of science, dealing with cells and living organisms. However, recourse to biological entities and their causal interactions is not sufficient to explain all biological phenomena, and biological explanations cannot be complete explanations.
On the contrary, physical theories are said to be complete in the sense that any phenomenon can theoretically be described in terms of causes and physical laws. The “causal” (concerning the totality of the causes) and “nomological” (concerning the totality of the laws) completeness of physics is what justifies, for the supporter of reductionist naturalism, that the descriptions that physics gives us of the world are those which best present to us what “really” things are.
However, the interest of adopting this reductionist attitude remains a very controversial point within naturalism itself, especially for functionalist philosophers like Jerry Fodor or Hilary Putnam.
Philosophical naturalism is based on an optimistic attitude about the possibility of knowing the world. Although it is sometimes referred to as “metaphysical”, this does not necessarily mean a speculative theory relating to a domain of being presumed to exist beyond the empirical world, and thereby unknowable, but the development of general categories that seek to capture the “reality” of the empirical world. If there is indeed for the naturalist a world whose existence does not depend on our experience, we nevertheless have access to it on the cognitive level thanks to the natural sciences, and it is the knowledge thus acquired that allows us to understand the very nature of our experience.
Man and the entire universe are therefore capable, in principle, of being explained by the natural sciences. Unlike materialism, naturalism is therefore a more methodological than ontological conception. He maintains that there is no a priori limit to scientific explanation. Even if there are de facto limits to scientific development at a given time, nothing excludes nature from being fully intelligible and there are no definitive limits to the extension of scientific knowledge. Also, naturalism implies a form of scientific optimism associated with a “reductionist” conception of knowledge, a double aspect of naturalism that Claude Bernard already explained very well in 1865 in the field of biology:
“Today we distinguish three orders of properties manifested in the phenomena of living beings: physical properties, chemical properties and vital properties. This last denomination of vital properties is itself only provisional; because we call vital the organic properties which we have not yet been able to reduce to physico-chemical considerations; but there is no doubt that we will one day get there.”
Naturalism and philosophy of mind
From the 17th century, with the development of the natural sciences, a number of philosophers such as Descartes or Spinoza have proposed different ways of understanding the place that the mind occupies in the physical world. With the emergence of the philosophy of mind in the 1950s, many attempts were made to explain mental life in terms of natural processes.
A common solution in the 1960s was to identify psychological states (perceptions, sensations, desires, beliefs, etc.) with neurophysiological states or processes in the brain. This strongly naturalistic and reductionist conception came to be known as the theory of mind-brain identity and was notably defended by the philosophers Jack Smart and Ullin Place. They claim that neuroscience can enable us to understand how certain structures and neurophysiological processes in the brain are similar to a mental life for us. We can consider that most neuroscientists explicitly or tacitly adhere to the theory of mind-brain identity (Jean-Pierre Changeux, António Damásio, Stanislas Dehaene, in particular, defend this position).
The mind-brain identity theory was widely criticized in the 1960s and 1970s for its inability to account for the multiple realization of mental phenomena, which can be generated by a variety of different mechanisms. If, for example, we believe that an animal lacking the C nerve fibers of the sensory cortex (associated in humans and mammals with pain) can still suffer, as is apparently the case in the octopus or other invertebrates, then it is wrong to say that the concepts of pain and C fibers really refer to the same thing. This critique of the theory of identity constituted a point of agreement to seek other solutions to the body-mind problem in a naturalistic but non-reductionist framework. Among them, functionalism (Jerry Fodor, Hilary Putnam), anomalous monism (Donald Davidson) and instrumentalism (Daniel Dennett) today constitute naturalist theories of the mind to which a large number of naturalist philosophers adhere. not adopting the reductionist attitude.
Naturalism and ethics
In its radical version, naturalism refuses any epistemological break or any insurmountable logical gap between natural facts and values, which can be explained naturally. However, the explanation of a fact does not constitute its justification, and philosophical naturalism has no prescriptive character: it does not claim to say what must be or what must be done. The moral or political doctrines which attempt to justify themselves on the basis of theses relating to naturalism (social Darwinism, eugenics, certain forms of ecologism) therefore constitute, in this sense, excesses.
Traditionally, philosophical naturalism leans towards utilitarianism or hedonism insofar as it rejects any transcendent moral or political principle (divine will, unconditional moral laws, reason superior to the interests of individuals). If there is a specificity of naturalistic ethics, it is not in a particular moral or deontological doctrine that it can appear, but rather in a certain relation to ethics and politics, both conceived as complex strategies aimed at improving the human condition.
Includes texts translated from Wikipedia