Evolution and ontological realism: a critical interpretation

Abstract

The relationship between biology and metaphysics has always been agonistic ever since biology advanced as an autonomous science through Darwin in the 19th century. On one hand, this can be viewed as an outcome of biologists' collective e orts to defend the claim that biology is an autonomous and independent branch of natural science. Justi cation to this claim presupposes the apparent seclusion of biology from not only other branches of science but also philosophy; especially, metaphysics. On the other hand, it is shadowed by the principles of mechanism that are culminated in physicalism. The latter aims at determinate knowledge of the phenomena in nature whose only context of explanation is descriptive. Metaphysical terminology in fact holds prescriptive nature; hence, biologists think it is necessary to disassociate metaphysics from biology in order to attain determinism[in terms of knowledge and explanation]. Not only biologists but also some philosophers of biology express the necessity of biology's isolation from metaphysics. Even some general philosophers of science nd it hard to think about the alliance of science with metaphysics, although the deterministic tone of explana-tion of science is modulated after the fall of positivism. However, the justi cations for the centuries-old anti-metaphysical resistance, in philosophy, mostly go on par with the trends in the Mechanistic tradition as well as the veri cation principle of positivism whose main strategy was to eliminate metaphysics. That is, philosophers inclined to the rigidity of conventional philosophy of science still consider that positivism was the marginal end of metaphysics. But, in fact, positivism was not an endpoint but a dividing line between traditional and new metaphysics. Deployment of self-referential concepts as the decimal points of backwardcausation, to conquer the fear of in nite regress, was the central strategy of traditional metaphysics. Such concepts are ontologically uncertain i.e., we cannot make any existential claim concerning the underlying entities these concepts refer. Because of this, scientists nd di culty in accommodating them in the descriptions of the world. For science, all phenomena fall within the boundary of causation and there could be no phenomena without a reason. The terms or concepts in any scienti c explanation must t into the framework of the context of explanation. That means, an account of a particular phenomenon rightly describes it and the terms/concepts it used in the description must have an independent explanation outside of that description. On the contrary, traditional metaphysics relies on the a priori concepts to explain phenomena in nature. The noumenal (things-inthemselves) nature of such concepts is devoid of any explanation,i.e., they existwith complete independence [mind independent]. We must understand that the anti-metaphysical claims which follow Mechanistic/positivist schemes generally target this noumenal nature of concepts. The anti-metaphysical movements have gained a rapid momentum, after Descartes, through Mechanism (Mechanicism, for Dupre 2017) in the natural phiiiilosophy. The philosophers of science, especially the rigid group, restored the momentum by igniting it with `reduction' and `downward causation'. It is remarked that up until 50 years ago, the philosophy of science was actually the philosophy of physical science (Takacs & Ruse 2013, 5). This is pointing towards another fact that biology was marginalized as secondary science. Mechanism and physicalism both have tried to restrain biology within the limits of determinism. One may wonder by realizing that biology was not recognized as a unique science in the framework of natural science and this was mirrored in the philosophy of science.All these lead us to the point that successful theories of physical science have sewn the determinate shroud of science. Determinism has played a major role in shaping the anti-metaphysical thought in science and philosophy. The possibility of determinism indeed is subjected to the compartmentalization of phenomena, i.e., the creation of de nite boundaries of explanation in science. This strategy is visible even in the early Mechanistic biology of Descartes. Based on the functional analogy he put forth the machine metaphor: organism-the machine. In such similar e orts in the later periods, we can see Mechanists attempt to isolate instances from their history. `Reductionism' and `downward causation' are essentially the markers of constructed boundaries of natural phenomena.The realist assertion-condition in general philosophy of science supposedly states that theories/explanations based on the aforementioned principles are true in their descriptions of reality. The underlying belief with this kind of claim is that the boundaries of objects/phenomena, which science accredits, display the genuine joints in reality. Unlike the case of physical science, one cannot easily mark the boundaries of explanation in biology. This is so because biology is bound by its history; in other words, the understanding of organic life does nothave isolated instances. It carries its history along with its explanations. That means the condition of existence, of biological entities, play a signi cant role in biological explanations. Taking this into consideration, it is argued here that instead of downward causation one can appropriately rely on backward causation in biology [historicity]. This historical relatedness plays a key role in understanding the metaphysics of science. The best way to establish this claim is to study the entities which are theoretically important in science. Successful scienti c theories are ontologically committed to the existence of entities they describe. Some theories postulate entities exhibiting ontologically indeterminate nature. In such case, all the interpreters of science may not assert the validity/truth of a particular theory. Some of them express skepticism over the claim that the theory rightly describes the reality `out there'. The inde nite nature of existence of suchtheoretically important entities calls for another discussion of the metaphysics of science. Broadly speaking, the ontological aspect of entities described in scienti c theories is the carrier of metaphysics. The ontology of scienti c theories possesses entities other than physical or observable entities. Based on this, some philosophers have been \forced to admit that nominalism is too austere an ontological doctrine to do justice to science" (Sober 1981, 147). Nominalism thus responds to realism in such a way that there are no such entities, say, for instance, gene, exist in nature; such concepts are names used for pragmatic purposes. This kind of anti-realist claim cannot be true entirely because successful scienti c models support the theories which talk about unobservables. Of course, our sense organs play signi cant roles in framing our ontology of the world. However, the belief that they are the only reliable means is wrongheaded. Getting back to ontology, it is commonly believed that ontology is the forgotten or repressed element in our present-day philosophy is what science vborrowed from philosophy (Grosz 2002, 38). The point is that ontological aspects acquire more attention than the mainstream metaphysics in scienti c theories. It is remarkable to note that the metaphysics of biology, both in its philosophical and scienti c outlook, has been shaped by the ontological aspects of biological entities.Even though biology confronts an inherent dialectical situation, it holds a pride of place in natural science and gets more philosophical attention nowadays. The dialectic is that \on the one hand, it is a marginal science since the biosphere forms no more than a tiny part of the universe; on the other hand, it is central because it deals with what counts most-life, including human life" (Possenti 2002, 38). Once we start talking about biology and its metaphysics, it is inappropriate omitting the three philosophical approaches-Aristotelian, Cartesian, and Kantianto the problems of life (Weber 2018). Their contributions are phenomenal to biology [natural philosophy] in its pre-scienti c phase. Aristotle addressed the problems of life by explaining the condition and nature of existence of living things; his biological explanations are vitalistic because of the supposition of the inner principle of Soul. Descartes' mechanistic biology came into the picture by abandoning the vital elements of Aristotelian biology. He addressed biologicalissues with Mechanistic principles because, for him, organisms are analogous to `mechanisms'. In Kantian biology, organisms were considered as organizations with default formative power. These thinkers were more concerned about the existential aspects of living things; hence, we can tie them together with the thread of ontology though they belong to di erent epistemic traditions. Pre-Darwinian biology was mostly concerned about the dependent-relation of phenomena and most of the biologists in that tradition had possessed a belief onthe necessity of an ultimate ontological ground. The general trend in the philosophy of biology, i.e., bracketing pre-Darwinian biology as creationist, reveals that the pre-Darwinians had an implicit goal of exploring the `where from' aspect of the biological phenomena. From Aristotle to Lamarck through Linnaeus and Erasmus, the necessity of a metaphysical grounding is implicit in their accounts of biological phenomena. This can be seen as their persuasion towards the explanatory dependence on a prime cause. This belief on the necessity of ontological dependence has been expunged by Darwin through his evolutionary chance explanations. He had substituted teleology and the prime cause by chance which is the prerequisite epistemological condition of his theory. Chance is not an antonym of cause because it is implicit in evolution theory that there is cause but it is tentatively indeterminate. Darwin had abandoned or removed the traditional metaphysical aspects from biology but at the same time he, like other naturalists, opened up thepossibility of a di erent kind of metaphysics in biology. The collective e orts for the rejection of metaphysics in modern science were actually setting up a scenario where ontology plays a substantial role. This is the second context of metaphysics in science corresponding to the post-positivist metaphysics in philosophy. The focal question of this new context of metaphysics has been framed ontologically and it is, `what there is'. Ontology is the study of the entities and their conditions of existence. Philosophers who were concerned about the biological issues were already in place. The analysis of issues in biology concerning its concepts helped us in understanding how metaphysics was rejuvenated in philosophy and science after the fall of the traditional metaphysics.If we pose the ontological question `what there is' in the context of biology, it is hard to deny the existence of life and species because successful theories like evolution theory have committed to their existence. While addressing the abovequestion a biologist will de nitely utter \Yes, there is life and species". The ontological investigation does not end up with this; it goes on to the next level by asking the conditions of existence of life and species. Biologists face di culty in addressing this task. Having a determinate answer to this second level of ontological inquiry is a hard task. A determinate answer is beyond imagination. This is so because the aforementioned concepts are representing some real underlying entities whose condition of existence is beyond our reach. This mind-independence condition is actually the seat of metaphysics in biology.As noted above, metaphysics was rejuvenated in science through ontology which is an unavoidable part of it. In the new phase, the aspects of metaphysics come with the investigations of ontology [condition of existence] of phenomena. The analysis of the three important concepts in biology, i.e., life, organism, and species, and the ontological discussions about them has re-explored the nature of metaphysics in the [evolutionary] biology. In addition, it became clear that the metaphysics of biology rightly mirrors the metaphysics of science. The thesis is concerned with these entities because they are the fundamental pillars without a unique de nition in biology. Without these concepts, biology will cease to exist. Analysis of the ontological issues of these entities has revealed that there is an undeniable relation between ontology and realism in biology. A proper philosophical idea/thesis was required to assert such a relation. The choice of `ontologicalrealism' prima facie attests to the relation between ontology and realism. Hence, the discussions in this thesis stemmed from the ground of ontological realism. Ontological realism, here, is explained as a doctrine that argues for the independent existence of ontology of entities postulated by successful scienti c theories.