Philosophy of biology

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The philosophy of biology is a subfield of philosophy of science, which deals with epistemological, metaphysical, and ethical issues in the biological and biomedical sciences. Although philosophers of science and philosophers generally have long been interested in biology (e.g., Aristotle, Descartes, and Kant), philosophy of biology only emerged as an independent field of philosophy in the 1960s and 1970s, associated with the research of David Hull. [1] Philosophers of science then began paying increasing attention to biology, from the rise of Neodarwinism in the 1930s and 1940s to the discovery of the structure of DNA in 1953 to more recent advances in genetic engineering. Other key ideas include the reduction of all life processes to biochemical reactions, and the incorporation of psychology into a broader neuroscience.

Contents

Overview

Philosophers of biology examine the practices, theories, and concepts of biologists with a view toward better understanding biology as a scientific discipline (or group of scientific fields). Scientific ideas are philosophically analyzed and their consequences are explored. Philosophers of biology have also explored how our understanding of biology relates to epistemology, ethics, aesthetics, and metaphysics and whether progress in biology should compel modern societies to rethink traditional values concerning all aspects of human life. It is sometimes difficult to separate the philosophy of biology from theoretical biology.

Ideas drawn from philosophical ontology and logic are being used by biologists in the domain of bioinformatics. Ontologies such as the Gene Ontology [4] are being used to annotate the results of biological experiments in model organisms in order to create logically tractable bodies of data for reasoning and search. The ontologies are species-neutral graph-theoretical representations of biological types joined together by formally defined relations. [5]

Philosophy of biology has become a visible, well-organized discipline, with its own journals, conferences, and professional organizations. The largest of the latter is the International Society for the History, Philosophy, and Social Studies of Biology (ISHPSSB). [6]

Biological laws and autonomy of biology

A prominent question in the philosophy of biology is whether biology can be reduced to lower-level sciences such as chemistry and physics. Materialism is the view that every biological system including organisms consists of nothing except the interactions of molecules; it is opposed to vitalism. As a methodology, reduction would mean that biological systems should be studied at the level of chemistry and molecules. In terms of epistemology, reduction means that knowledge of biological processes can be reduced to knowledge of lower-level processes, a controversial claim. [7]

Holism in science is the view that emphasizes higher-level processes, phenomena at a larger level that occur due to the pattern of interactions between the elements of a system over time. For example, to explain why one species of finch survives a drought while others die out, the holistic method looks at the entire ecosystem. Reducing an ecosystem to its parts in this case would be less effective at explaining overall behavior (in this case, the decrease in biodiversity). As individual organisms must be understood in the context of their ecosystems, holists argue, so must lower-level biological processes be understood in the broader context of the living organism in which they take part. Proponents of this view cite our growing understanding of the multidirectional and multilayered nature of gene modulation (including epigenetic changes) as an area where a reductionist view is inadequate for full explanatory power. [8]

All processes in organisms obey physical laws, but some argue that the difference between inanimate and biological processes is that the organisation of biological properties is subject to control by coded information. This has led biologists and philosophers such as Ernst Mayr and David Hull to return to the strictly philosophical reflections of Charles Darwin to resolve some of the problems which confronted them when they tried to employ a philosophy of science derived from classical physics. The old positivist approach used in physics emphasised a strict determinism and led to the discovery of universally applicable laws, testable in the course of experiment. It was difficult for biology to use this approach. [9] Standard philosophy of science seemed to leave out a lot of what characterised living organisms - namely, a historical component in the form of an inherited genotype.

Philosophers of biology have also examined the notion of teleology in biology. Some have argued that scientists have had no need for a notion of cosmic teleology that can explain and predict evolution, since one was provided by Darwin. But teleological explanations relating to purpose or function have remained useful in biology, for example, in explaining the structural configuration of macromolecules and the study of co-operation in social systems. By clarifying and restricting the use of the term 'teleology' to describe and explain systems controlled strictly by genetic programmes or other physical systems, teleological questions can be framed and investigated while remaining committed to the physical nature of all underlying organic processes. While some philosophers claim that the ideas of Charles Darwin ended the last remainders of teleology in biology, the matter continues to be debated. Debates in these areas of philosophy of biology turn on how one views reductionism more generally. [10] [11] [12] [13]

Ethical implications of biology

Sharon Street claims that contemporary evolutionary biological theory creates what she calls a “Darwinian Dilemma” for realists. She argues that this is because it is unlikely that our evaluative judgements about morality are tracking anything true about the world. Rather, she says, it is likely that moral judgements and intuitions that promote our reproductive fitness were selected for, and there is no reason to think that it is the truth of these moral intuitions which accounts for their selection. She notes that a moral intuition most people share, that someone being a close family member is a prima facie good reason to help them, happens to be an intuition likely to increase reproductive fitness, while a moral intuition almost no one has, that someone being a close family member is a reason not to help them, is likely to decrease reproductive fitness. [14]

David Copp responded to Street by arguing that realists can avoid this so-called dilemma by accepting what he calls a “quasi-tracking” position. Copp explains that what he means by quasi tracking is that it is likely that moral positions in a given society would have evolved to be at least somewhat close to the truth. He justifies this by appealing to the claim that the purpose of morality is to allow a society to meet certain basic needs, such as social stability, and a society with a successful moral codes would be better at doing this. [15]

Other perspectives

One perspective on the philosophy of biology is how developments in modern biological research and biotechnologies have influenced traditional philosophical ideas about the distinction between biology and technology, as well as implications for ethics, society, and culture. An example is the work of philosopher Eugene Thacker in his book Biomedia. [16] Building on current research in fields such as bioinformatics and biocomputing, as well as on work in the history of science (particularly the work of Georges Canguilhem, Lily E. Kay, and Hans-Jörg Rheinberger), Thacker defines biomedia as entailing "the informatic recontextualization of biological components and processes, for ends that may be medical or non-medical...biomedia continuously make the dual demand that information materialize itself as gene or protein compounds. This point cannot be overstated: biomedia depend upon an understanding of biological as informational but not immaterial." [17]

Some approaches to the philosophy of biology incorporate perspectives from science studies and/or science and technology studies, anthropology, sociology of science, and political economy. This includes work by scholars such as Melinda Cooper, Luciana Parisi, Paul Rabinow, Nikolas Rose, and Catherine Waldby. [18] [19] [20] [21]

Philosophy of biology was historically associated very closely with theoretical evolutionary biology, but more recently there have been more diverse movements, such as to examine molecular biology. [22]

Scientific discovery process

Research in biology continues to be less guided by theory than it is in other sciences.[ dead link ] [23] This is especially the case where the availability of high throughput screening techniques for the different "-omics" fields such as genomics, whose complexity makes them predominantly data-driven. Such data-intensive scientific discovery is by some considered to be the fourth paradigm, after empiricism, theory and computer simulation. [24] Others reject the idea that data driven research is about to replace theory. [25] [26] As Krakauer et al. put it: "machine learning is a powerful means of preprocessing data in preparation for mechanistic theory building, but should not be considered the final goal of a scientific inquiry." [27] In regard to cancer biology, Raspe et al. state: "A better understanding of tumor biology is fundamental for extracting the relevant information from any high throughput data." [28] The journal Science chose cancer immunotherapy as the breakthrough of 2013. According to their explanation a lesson to be learned from the successes of cancer immunotherapy is that they emerged from decoding of basic biology. [29]

Theory in biology is to some extent less strictly formalized than in physics. Besides 1) classic mathematical-analytical theory, as in physics, there is 2) statistics-based, 3) computer simulation and 4) conceptual/verbal analysis. [30] Dougherty and Bittner argue that for biology to progress as a science, it has to move to more rigorous mathematical modeling, or otherwise risk to be "empty talk". [31]

In tumor biology research, the characterization of cellular signaling processes has largely focused on identifying the function of individual genes and proteins. Janes [32] showed however the context-dependent nature of signaling driving cell decisions demonstrating the need for a more system based approach. [33] The lack of attention for context dependency in preclinical research is also illustrated by the observation that preclinical testing rarely includes predictive biomarkers that, when advanced to clinical trials, will help to distinguish those patients who are likely to benefit from a drug. [34]

The Darwinian dynamic and the origin of life

Organisms that exist today, from viruses to humans, possess a self-replicating informational molecule (genome) that is either DNA (most organisms) or RNA (as in some viruses), and such an informational molecule is likely intrinsic to life. Probably the earliest forms of life were likewise based on a self-replicating informational molecule (genome), perhaps RNA [35] [36] or an informational molecule more primitive than RNA or DNA. It has been argued [37] that the evolution of order in living systems and in particular physical systems obey a common fundamental principle that was termed the Darwinian dynamic. This principal was formulated by first considering how macroscopic order is generated in a simple non-biological system far from thermodynamic equilibrium, and subsequently extending consideration to short, replicating RNA molecules. The underlying order-generating process was concluded to be basically similar for both types of systems. [37] [38]

Journals and professional organizations

Journals

Professional organizations

See also

Related Research Articles

<span class="mw-page-title-main">Neural Darwinism</span> Theory in neurology

Neural Darwinism is a biological, and more specifically Darwinian and selectionist, approach to understanding global brain function, originally proposed by American biologist, researcher and Nobel-Prize recipient Gerald Maurice Edelman. Edelman's 1987 book Neural Darwinism introduced the public to the theory of neuronal group selection (TNGS), a theory that attempts to explain global brain function.

<span class="mw-page-title-main">Reductionism</span> Philosophical view explaining systems in terms of smaller parts

Reductionism is any of several related philosophical ideas regarding the associations between phenomena which can be described in terms of simpler or more fundamental phenomena. It is also described as an intellectual and philosophical position that interprets a complex system as the sum of its parts.

<span class="mw-page-title-main">Teleology</span> Thinking in terms of destiny or purpose

Teleology or finality is a branch of causality giving the reason or an explanation for something as a function of its end, its purpose, or its goal, as opposed to as a function of its cause. James Wood, in his Nuttall Encyclopaedia, explained the meaning of teleology as "the doctrine of final causes, particularly the argument for the being and character of God from the being and character of His works; that the end reveals His purpose from the beginning, the end being regarded as the thought of God at the beginning, or the universe viewed as the realisation of Him and His eternal purpose."

<span class="mw-page-title-main">Computational biology</span> Branch of biology

Computational biology refers to the use of data analysis, mathematical modeling and computational simulations to understand biological systems and relationships. An intersection of computer science, biology, and big data, the field also has foundations in applied mathematics, chemistry, and genetics. It differs from biological computing, a subfield of computer science and engineering which uses bioengineering to build computers.

Primordial soup, also known as prebiotic soup, is the hypothetical set of conditions present on the Earth around 3.7 to 4.0 billion years ago. It is an aspect of the heterotrophic theory concerning the origin of life, first proposed by Alexander Oparin in 1924, and J. B. S. Haldane in 1929.

<span class="mw-page-title-main">Mathematical and theoretical biology</span> Branch of biology

Mathematical and theoretical biology, or biomathematics, is a branch of biology which employs theoretical analysis, mathematical models and abstractions of living organisms to investigate the principles that govern the structure, development and behavior of the systems, as opposed to experimental biology which deals with the conduction of experiments to test scientific theories. The field is sometimes called mathematical biology or biomathematics to stress the mathematical side, or theoretical biology to stress the biological side. Theoretical biology focuses more on the development of theoretical principles for biology while mathematical biology focuses on the use of mathematical tools to study biological systems, even though the two terms are sometimes interchanged.

<span class="mw-page-title-main">Emergentism</span> Philosophical belief in emergence

Emergentism is the belief in emergence, particularly as it involves consciousness and the philosophy of mind. A property of a system is said to be emergent if it is a new outcome of some other properties of the system and their interaction, while it is itself different from them. Within the philosophy of science, emergentism is analyzed both as it contrasts with and parallels reductionism. This philosophical theory suggests that higher-level properties and phenomena arise from the interactions and organization of lower-level entities yet are not reducible to these simpler components. It emphasizes the idea that the whole is more than the sum of its parts.

In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection.

<span class="mw-page-title-main">Unit of selection</span> Biological entity within the hierarchy of biological organization

A unit of selection is a biological entity within the hierarchy of biological organization that is subject to natural selection. There is debate among evolutionary biologists about the extent to which evolution has been shaped by selective pressures acting at these different levels.

Teleonomy is the quality of apparent purposefulness and of goal-directedness of structures and functions in living organisms brought about by natural processes like natural selection. The term derives from two Greek words, τέλος, from τελε-, and νόμος nomos ("law"). Teleonomy is sometimes contrasted with teleology, where the latter is understood as a purposeful goal-directedness brought about through human or divine intention. Teleonomy is thought to derive from evolutionary history, adaptation for reproductive success, and/or the operation of a program. Teleonomy is related to programmatic or computational aspects of purpose.

Evolutionary ethics is a field of inquiry that explores how evolutionary theory might bear on our understanding of ethics or morality. The range of issues investigated by evolutionary ethics is quite broad. Supporters of evolutionary ethics have argued that it has important implications in the fields of descriptive ethics, normative ethics, and metaethics.

<span class="mw-page-title-main">Structuralism (biology)</span> Attempt to explain evolution by forces other than natural selection

Biological or process structuralism is a school of biological thought that objects to an exclusively Darwinian or adaptationist explanation of natural selection such as is described in the 20th century's modern synthesis. It proposes instead that evolution is guided differently, by physical forces which shape the development of an animal's body, and sometimes implies that these forces supersede selection altogether.

<span class="mw-page-title-main">Biological organisation</span> Hierarchy of complex structures and systems within biological sciences

Biological organisation is the organisation of complex biological structures and systems that define life using a reductionistic approach. The traditional hierarchy, as detailed below, extends from atoms to biospheres. The higher levels of this scheme are often referred to as an ecological organisation concept, or as the field, hierarchical ecology.

In evolutionary biology, function is the reason some object or process occurred in a system that evolved through natural selection. That reason is typically that it achieves some result, such as that chlorophyll helps to capture the energy of sunlight in photosynthesis. Hence, the organism that contains it is more likely to survive and reproduce, in other words the function increases the organism's fitness. A characteristic that assists in evolution is called an adaptation; other characteristics may be non-functional spandrels, though these in turn may later be co-opted by evolution to serve new functions.

<span class="mw-page-title-main">Living systems</span> Multiple interactions and regulation of life forms with their environment

Living systems are life forms treated as a system. They are said to be open self-organizing and said to interact with their environment. These systems are maintained by flows of information, energy and matter. Multiple theories of living systems have been proposed. Such theories attempt to map general principles for how all living systems work. Toy story

<span class="mw-page-title-main">Lloyd Demetrius</span> American mathematician

Lloyd A. Demetrius is an American mathematician and theoretical biologist at the Department of Organismic and Evolutionary biology, Harvard University. He is best known for the discovery of the concept of evolutionary entropy, a statistical parameter that characterizes Darwinian fitness in models of evolutionary processes at various levels of biological organization – molecular, organismic and social. Evolutionary entropy, a generalization of the Gibbs-Boltzmann entropy in statistical thermodynamics, is the cornerstone of directionality theory, an analytical study of evolution by variation and selection. The theory has applications to: a) the development of aging and the evolution of longevity; b) the origin and progression of age related diseases such as cancer, and neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease; c) the evolution of cooperation and the spread of inequality.

An organism is any living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Many criteria, few of them widely accepted, have been proposed to define what an organism is. Among the most common is that an organism has autonomous reproduction, growth, and metabolism. This would exclude viruses, despite the fact that they evolve like organisms. Other problematic cases include colonial organisms; a colony of eusocial insects is organised adaptively, and has germ-soma specialisation, with some insects reproducing, others not, like cells in an animal's body. The body of a siphonophore, a jelly-like marine animal, is composed of organism-like zooids, but the whole structure looks and functions much like an animal such as a jellyfish, the parts collaborating to provide the functions of the colonial organism.

Universal Darwinism, also known as generalized Darwinism, universal selection theory, or Darwinian metaphysics, is a variety of approaches that extend the theory of Darwinism beyond its original domain of biological evolution on Earth. Universal Darwinism aims to formulate a generalized version of the mechanisms of variation, selection and heredity proposed by Charles Darwin, so that they can apply to explain evolution in a wide variety of other domains, including psychology, linguistics, economics, culture, medicine, computer science, and physics.

<span class="mw-page-title-main">Teleology in biology</span> Use of language of goal-directedness in the context of evolutionary adaptation

Teleology in biology is the use of the language of goal-directedness in accounts of evolutionary adaptation, which some biologists and philosophers of science find problematic. The term teleonomy has also been proposed. Before Darwin, organisms were seen as existing because God had designed and created them; their features such as eyes were taken by natural theology to have been made to enable them to carry out their functions, such as seeing. Evolutionary biologists often use similar teleological formulations that invoke purpose, but these imply natural selection rather than actual goals, whether conscious or not. Some biologists and religious thinkers held that evolution itself was somehow goal-directed (orthogenesis), and in vitalist versions, driven by a purposeful life force. With evolution working by natural selection acting on inherited variation, the use of teleology in biology has attracted criticism, and attempts have been made to teach students to avoid teleological language.

<span class="mw-page-title-main">Alternatives to Darwinian evolution</span> List of alternatives to Darwinian natural selection

Alternatives to Darwinian evolution have been proposed by scholars investigating biology to explain signs of evolution and the relatedness of different groups of living things. The alternatives in question do not deny that evolutionary changes over time are the origin of the diversity of life, nor that the organisms alive today share a common ancestor from the distant past ; rather, they propose alternative mechanisms of evolutionary change over time, arguing against mutations acted on by natural selection as the most important driver of evolutionary change.

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