In philosophy, realism refers to the position which affirms the existence of an external reality independent of our mind. Realism affirms both the existence and the independence of the world. Existence means that there is a world outside the subject, and independence means that this world does not need to be connected to a subject in order to exist. Realism asserts that the world is one thing and that our representations are another.
So conceived, realism is opposed to idealism, which maintains that the world is only a representation and does not have an autonomous existence. On the contrary, when we take a realistic stand, we are arguing that the existence of the world precedes the existence of our mind and that the world continues to exist without it.
A person can be realistic about the existence and independence of some things and be anti-realistic about other things. The realist about universals, for example, considers universals to be entities that exist in the world, but he may consider, like the Platonists, that the individual beings who exemplify them have no existence as such. In this case he is opposed to the nominalist, who maintains a realistic position concerning only individuals.
The different versions of realism
Realism can designate various philosophical positions according to the entities or characteristics whose reality is postulated or according to the fields where this position is claimed. Philosophical realism includes at least four components: 1 / ontological, metaphysical, 2 / gnoseological, epistemological, 3 / semantics and 4 / ethics.
We speak of metaphysical realism, or ontological realism, when the realist position is applied to entities whose existence is postulated by a philosophical theory or doctrine. This thesis is not supposed to be verifiable, but it is presupposed whenever one claims to explore a world that preexists its discovery.
Epistemological realism, or gnoseological realism, is a theoretical position on the subject of knowledge, which considers that this relates to “real” objects external to the subject and independent of it. The gnoseological thesis that he understands implies being able to come to the knowledge of reality, at least partially and gradually. Scientific realism is epistemological realism and is tacitly accepted by all who believe that knowledge offers us a true representation of how the world is, independent of mind.
Semantic realism maintains that propositions or expressions articulated in a language designate, when they are true, facts or states of affairs occurring in the world. A statement is true when what it describes is the description of certain things or events that exist or happen in the world independent of language. Semantic realism involves a metaphysical conception of the reference of words or linguistic expressions.
Finally, ethical realism maintains that there are moral truths which correspond to moral facts. We also speak of moral naturalism to qualify this position.
“Minimal” or “structural” realism
The mathematician Henri Poincaré proposed one of the very first arguments in favor of what is today called “structural realism“, following the commentator Elie Zahar who made it a precursor of this current. According to Poincaré, the scientific fact is a simplified and practical translation of the empirical fact: “The scientific fact is only the raw fact translated into a convenient language”. Poincaré thus exposes the idea that experience is already structured by its relationships and that the human mind constructs science from this pre-structuring. He seeks to refute the radical version of conventionalism and pragmatism of Édouard Le Roy, according to which, “[…] scientific facts, and a fortiori, laws are the artificial work of the scientist; science cannot therefore teach us anything about the truth, it can only serve us as a rule of action ”.
Henri Poincaré therefore defends a minimal form of realism, compatible with the conventionalism with which it is traditionally associated, and which is based on the fact that we have direct epistemic access only to our perceptions, which are private and not communicable. The only thing we are able to convey are the relationships between our perceptions. Thus, two people cannot be sure that they perceive color tints the same, but they can still agree that two objects are the same shade, or that an object is darker than it is. another. To the extent that objective knowledge must be public and intersubjective, it can only be based on what is transmissible; it follows that only the relationships between experiences have an objective value and can be a source of knowledge. If it is accepted that a knowledge of reality is possible, it must be a knowledge that relates to its structure, and not to the contents of reality themselves.
Realism and anti-realism
According to Michael Devitt, metaphysical realism is an “irresistible doctrine” and there is no argument that could compel us to give it up. For the anti-realists, on the contrary, like Bas van Fraassen, metaphysical realism is a dogmatic position which it is impossible to verify, and which thus turns out to be useless on the gnoseological level. According to Hilary Putnam, metaphysical realism requires the adoption of a “divine point of view”, necessarily illusory because it is illusory to believe that we can access a world completely independent of particular conditions (social, psychological or cultural ) of its representation.
According to George Berkeley, a classic figure of anti-realism, if it is problematic to posit the existence of a reality independent of the mind, it is because existence itself is posed by a subject. The existence of the world implies that of the subject who experiences it. There is indeed a reality of the world, but this reality is necessarily immaterial in the sense that nothing can exist independently of a subject of perception.
Realism in Eastern thought
Among the Buddhists, the school of Sarvâstivâdin of Kashmir “poses itself as resolutely realistic and even pan-realistic by admitting the existence of the outside world and by posing the real existence of things, even admitting the real existence of past phenomena, present and future. By “real thing” (Sanskrit bhâva, Tibetan dngos-po), we must understand “that which is endowed with efficiency”, that is to say a phenomenon capable of performing a function within causality “.