Hierarchy, Form and Reality Gang Chen Department of Philosophy, Huazhong University of Science and Technology，Wuhan, 430074, China 摘要：现代科学对哲学所提供的最重要成就是一种层次的世界观，对世界层次结构的分析将 对形而上学和哲学具有明显的意义。夏法尔的论文“是否存在一个基础的层次？” 系统地 讨论了基础主义在这方面的工作及其面临的问题，在缺乏论证的情况下最后指出了一条非还 原主义的出路，我们可以把每一层都看作是等同的，承认它们都具有“存在共和国中的完全 公民权” 。本文将为此提供一个论证：将亚里士多德的形式理论应用于世界层次结构的分析， 发展出形式实在论，并以此来论证一种本体论的非还原主义以反对原子主义和物理主义；提 出一种因果作用的说明以反对副现象论；提出认识论的非还原主义以反对观念原子主义和认 识论还原主义。 Abstract: Scientific progress in the 20th century has shown that the structure of the world is hierarchical. A philosophical analysis of the hierarchy will bear obvious significance for metaphysics and philosophy in general. Jonathan Schaffer's paper, "Is There a Fundamental Level?", provides a systematic review of the works in the field, the difficulties for various versions of fundamentalism, and the prospect for the third option, i.e., to treat each level as ontologically equal. The purpose of this paper is to provide an argument for the third option, which is missing in Schaffer's paper. The author will apply Aristotle's theory of matter and form to the discussion of the hierarchy and develop a form realism, which will grant every level with "full citizenship in the republic of being." It is also an argument against ontological and epistemological reductionism. 1. Introduction The most significant scientific achievement for philosophy in the 20th century is the general view that the structure of our world is hierarchical. In one direction, astronomers have proved that the remote spiral nebulae are galaxies like our own Milky Way. Thus the Universe is one level bigger than the Milky Way, and consists of galaxies as islands. Some day in the future they may discover that there is more than one Big Bang. In the opposite direction, atomic physicists have shown that, while everything consists of molecules and atoms, the atoms are not atomic. They split the atoms and drilled down all the way through protons, neutrons and electrons, quarks and leptons, ... and finally to super strings. Although they have no way to prove that a super string has no internal structure, the tendency did lead us to postulate that it is an endless descending. After a long journey in both directions, one thing is for sure: our world is multi-layered, i.e., of a hierarchical structure of multiple levels. An analysis of the hierarchical model of the world definitely bears an obvious significance for metaphysics and for philosophy in general. 2. Schaffer on Fundamentalism Jonathan Schaffer's recent paper on NOǗS, "Is There a Fundamental Level?", does a systematic review of the works by philosophers as well as scientists. It provides the context of the problems and the entry point for the research in the field. As the title of the paper suggests, the focus of his attention is on fundamentality. According to Schaffer, fundamentalism consists of three theses: 1) the thesis of hierarchy, i.e., the world is hierarchical, stratified into levels; 2) the thesis of fundamentality, i.e., there is a bottom level which is fundamental; 3) the thesis of primacy, i.e., the bottom level is primarily real, other levels are only derivative (Schaffer 2003, p498). Schaffer leaves the first thesis intact, does not pay much attention to the third thesis, but thinks that the second thesis is the source of problem. Therefore, Schaffer’s key question is, “whether science is actually in the process of discovering atoms”, “whether science indicates atomism”, that is, whether the descending is finite or infinite (ibid, p502). From the current state of science, we do not know if quark or super string is the fundamental building block. But the history of science, as Schaffer admits, “is a history of finding ever-deeper structure” (ibid p503). Whenever we had found a fundamental building block, atoms or quarks for example, soon we always found that they have parts and an internal structure. Therefore it shows a tendency or a trajectory that the descending is infinite. However, the tendency or trajectory, like induction, is by no means a logical proof. Although I believe that there will never be a complete microphysics, since scientific inquiry will never come to an end, I do agree with Schaffer that we should remain agnostic about this issue. With the thesis of fundamentality in doubt, Schaffer proposed three options as outlets: 1) that a certain version of fundamentalism can be re-formulated without presupposing fundamentality, that is, a fundamentalism without fundamentality; 2) that there might be evidence for a fundamental something else, such as a fundamental supervenience base, which consists of more than one level; 3) that we treat each level as equal and grant them “a full citizenship in the republic of being”. After a detailed discussion of the options 1 and 2 by examining the four versions of fundamentalism (physicalism, Humean idea atomism, epiphenomenalism and atomism), Schaffer comes to the conclusion that the option 3 is the most desirable. In the end of his paper, Schaffer shows the possible benefit and prospect for the third option. The following quick comments are at our order: 1) Schaffer seems to think that only the second thesis of fundamentality is question begging. However, the thesis of primacy is based on the thesis of hierarchy and the thesis of fundamentality. If the thesis of fundamentality does not hold, the thesis of primacy loses its ground. If we cannot identity the fundamental level, no level is primary. 2) If there is an infinite descending in the hierarchy, it will pose a serious problem for fundamentalism; however, if there is indeed a complete microphysics, it does not prove that fundamentalism or reductionism is the only viable option. There might still be a room for non-reductionism, because it does not require an infinite descending. 3) Schaffer only points out the benefits and prospect for the third option, he provides no arguments for it. 4) Fundamentalism is a reductionist interpretation of the hierarchical worldview. There might be a non-reductionist interpretation of the hierarchy. That is, we accept the thesis of hierarchy, remain agnostic on the thesis of fundamentality, but deny the thesis of primacy. While Schaffer takes fundamentality as the focus of discussion, I think it is the issue of reduction that should be the real focus of discussion. Our key question is not whether there is a fundamental level, but the relation between two adjacent levels, namely, the relation is reductive or not. Therefore we move our attention from the thesis of fundamentality to the thesis of primacy. The purpose of this paper is to provide an argument for Schaffer’s third option, which is missing in Schaffer's own paper. Firstly I will extrapolate Aristotle’s theory of matter and form in the light of modern sciences, that is, to apply Aristotle's theory to the discussion of the hierarchy, and develop a form realism, which will grant every level with a "full citizenship in the republic of being". This is, at the same time, an argument against physicalism and atomism. Secondly I will approach the problem of causation and provide a theory of causation according to form realism, which constitutes an argument against epiphenomenalism. Finally I will shift the focus from ontological reductionism to epistemological reductionism and provide an argument against Humean idea atomism. 3. A Theory of Form Realism Fundamentalism is a well-established tradition in the history of philosophy. It actually dates back to the first Greek philosopher, Thales. The tradition continued to live on throughout history in the hands of other Ionian philosophers, atomists, materialists, reductionists, the advocators of mind-body identity theory, and eliminative materialists. However, there is another tradition, which started almost at the same time and runs parallel to the reductionist or fundamentalist tradition. It is the tradition of Pythagoras, Plato and Aristotle. They paid more attention to immaterial issues such as harmony, relations, structures and forms. Both Plato and Aristotle considered forms, however, Plato’s Forms are different from Aristotle’s forms. Plato’s Forms are ideal, perfect, universal and ante rem; while Aristotle’s forms are empirical, particular, individual and in re. If Plato is an objective idealist; Aristotle is more like a non-reductive physicalist in 20th century. As a metaphysical concept, I prefer Aristotle’s form to Plato’s Form, since Aristotle’s form is more compatible with the new progress in science, while Plato’s concept of Form, as another kind of form realism, runs against the achievements in modern science. It is ironic that modern science develops by breaking away from Aristotelian tradition. This is the case at least for Galileo, Descartes and Francis Bacon. However, to cure certain symptoms of modern science, we have to come back to Aristotle. I believe Aristotle’s metaphysics of matter and form is quite potential. While most philosophers are looking for some kind of fundamental building blocks for the world, Aristotle's theory explains not just what exists in the world, but why the world is like this. While most philosophers are pursuing a reductionist approach, Aristotle's form provides a hope for non-reductionism. I would like to start an argument at the middle level in the hierarchy of existence, i.e., the meso-cosmic objects of sensible magnitude. Let's take a chair for example. It has two components: the wood beams (matter) and the design of a chair (form). When I bought a chair from IKEA, it was hardly a chair. It came as a set of parts tightly packed in a flat box. It is not yet a chair. It was not in the form of a chair. You cannot sit on it. It became a chair only when I finished the assembly. As Aristotle points out, matter is the potentiality, form the actuality (Aristotle De Anima 412a10). The chair is a composite of matter (the wood beams) and form (the structure of the chair) (Aristotle Metaphysics 1013a25). Now the chair is an existence distinct from the existence of a box of wood beams. A chair is not identical to a box of wood beams. The wood beams arranged in certain form become a chair. Fundamentalists seem to think that the arrangement is not important. Aristotle definitely thought differently. Aristotle is absolutely right when he interpreted "matter" as "which in itself is not a this"; "form" as "essence, which is that precisely in virtue of which a thing is called a this" (Aristotle De Anima 412a6-9). A chair is a chair, not because it is made of wood beams. Since a chair can be made of steel or plastic; we also build a table or a house by wood beams. A chair is a chair because it is in the form of a chair. We can find ample examples for Aristotle’s thesis. The essence of Coca-cola is its formula of the secret ingredients, water, salt, and sugar. Form differentiates music from noise, water from ice, a diamond from graphite, a Nikon FM2 from a Leica M6, and a Honda Accord from a BMW 323i. When the neurons in a brain stop firing, the mind loses its existence. Form determines what is what. Form is an indispensable component of the reality. Form is immaterial but real. If we apply Aristotle’s theory of matter and form to the hierarchy of reality and keep going downward, we will get something unexpected. What is a wood beam? It is made of wood cells. A wood beam is a foot for the chair, because its wood cells are arranged in the form of a foot; a wood beam is an arm for the chair, because its wood cells are in the form of an arm. If we keep going downward further and further, we get the following diagram: Diagram: The Hierarchy of Reality. What implications can we draw from the diagram? On the ladder of the downward analysis, at each level, matter can always be further analyzed into forms and sub-matter. All that remains on the ladder are forms. Matter almost resolves into forms, though not completely if we assume that the descending is finite. Matter does not "vaporize" and disappear. It only "melts" down the ladder, with some residues: electrons and quarks or super strings, assuming they are not penetrable. If we think that only matter is real, then what exist in the world are nothing but electrons and quarks or super strings. The whole world is nothing but the arrangement or properties of electrons and quarks. If forms are not real, only matter matters, we can refuse to pay the bills for electricity, telephone, Internet service, etc., since nothing material flows into my house from those services. Music would be the same thing as noise. Software piracy would be perfectly legal, since we only duplicate the magnetic patterns on our own floppy disc. It does not sound right. It runs against most of our intuitions. Only by admitting the reality of forms, and looking upward, can we get the existence of everything in the world. If form is real, then a chair is not identical to a box of wood beams, because a chair is the wood beams plus something extra, i.e., the form of a chair. The reality of forms as something extra also explains why in a system is more than the totality of its parts. [Addition: Some people may say that two things are different, partly because they have different matter. The difference in matter is not a real difference, since the difference in matter at one level is still the difference in form at a lower level. Form is the sole reason that determines what is what. ] If a chair is not identical to a box of wood beams, what is the relationship between them? To name the relationship, we may employ the term "supervenience". This is a popular term in current philosophy. Leibniz is the first philosopher who began to use the term "supervenire" in his Latin text concerning his doctrine of relations. In the 1920s and the 1930s it was used by British Emergentists as a stylish variant of “emergence” in their doctrine of "emergent evolution", meaning a "non-reductive" relation. In 1952 it was introduced by R.M. Hare into ethics to describe the “non-reductive” relation between moral property and descriptive property. In 1970, Donald Davidson used the term to describe the “non-reductive” relation between mental property and physical property. Most of them employ the term in the sense of "non-reductive" relation, which conforms to the common sense meaning in the Oxford English Dictionary, that is, "to come on or occur as something additional or extraneous after something else". However, Kim in his criticism of Davidson argues that supervenience is a reductive relation. Though I am not on the side of reductionism, I do think that Kim has made a contribution to the concept of supervenience. In order to avoid the ambiguity in the discussion of supervenience, Kim clearly defines it as a mereological relation (Kim 1998, p15). The only problem is that, supervenience defined as a mereological relation may no longer be suitable to describe the relation between the mental and the physical. For a typical mereological relation, both relata are physical. A typical mereological ascending won’t give rise to the emergence of the mental. If we insist that the relation between the mental and the physical is a special kind of mereological relation, then we have to spell out the uniqueness in that special kind. Why for most merelogical relation the two relata are both physical, but for that special kind, one relatum is physical, the other is mental. Obviously the mere notion of “mereological relation” cannot explain the difference between the mental and the physical, why something has both mental and physical properties while some other thing only has physical properties. If a choice has to be made, here is mine. I will employ “supervenience” solely for the relation between a chair and its parts. “Emergence” is the dynamic process for the creation of supervenient; “supervenience” is the static relation between the supervenient and the subvenient after the process of emergence. Supervenience is naturally a mereological relation according to the etymological meaning of the term. Since I have argued that a chair is not identical to its parts, supervenience is a non-reductive relation. This choice thus combines two elements of the term, “non-reductive” and “mereological”. Therefore, supervenience is a non-reductive mereological relation. We have to choose another term to describe the relation between the mental and the physical. If we apply the term supervenience to describe the relation, the chair is the supervenient; the pile of wood beams is the subvenient. The chair supervenes on the pile of wood beams. Several levels down the ladder, an atom supervenes on protons, neutrons and electrons. Several levels up the ladder, a university supervenes on its departments. Since a chair is not identical to a box of wood beams, the relation between the two relata is not reductive. The chair is located somewhat higher on the ladder than its wood beams. It has one more extra real component, the form. However, can we say that the supervenient is a stronger existence than its subvenient since the supervenient has form as one more real component? If we admitted this, then electrons and quarks would have the weakest existence. Any particle physicist will definitely say no to the conclusion. Fundamentalists (atomists and physicalists) think that fundamental level is the only thing real, or at least more real than upper levels. If that were the case, then Milky Way and spiral nebulae would have the weakest existence or would not exist at all. This is obviously wrong. Therefore, I would say that supervenient and subvenient are equally real. The hierarchy as a whole is the totality of the reality. Each level is one layer of the reality. 4. How Causation Happens? Epiphenomenalism in philosophy of mind is the theory that the physical has a causal effect on the mental, but not vice versa. Epiphenomenalism as presented by Schaffer in the context of metaphysics has a slightly different version, that is, all causal powers inhere at the fundamental level. Epiphenomenalism seems to receive support from science. A professor of physics might also tell us that all causation happens via one or more of the four fundamental forces: 1) strong interaction where gluon is the agent, 2) weak interaction where neutrino is the agent, 3) electro-magnetic interaction where photon is the agent, and 4) gravitational interaction where graviton is the agent. Does this mean that causation happens only at the fundamental level? We should not jump to that conclusion instantly. New progress in science may prove that the four fundamental forces are not fundamental. With the thesis of fundamentality in trouble, the similar perplexing question that epiphenomenalism has no way to answer is, “What is the hierarchical level at which the causation really happens?” Has physics found the final causal agent and the lowest level of causation for us? Again, there are two possibilities. If we assume that we have not found the final causal agent and the lowest level of causation, it does not mean that our knowledge about causation is zero. We already have a lot of knowledge, based on causation at the macro level. If we assume that we have found the fundamental causal agent and the lowest level of causation, it is doubtful to say that causation happens only at the lowest level. Scientists, especially physicists, never hesitate to provide causal explanations at macro-levels. We already have conceivable causal accounts at many levels on the ladder of reality. Each one of them is unique. Now with form realism in hand, we face a different set of questions. Does form have any causal power? Is form involved in causation? Can we say that forms at macro levels play no role in causation? If form is real, it is better to assign some causal power to it. It is obviously not right to say that forms at macro levels play no causal role. Still take a chair for example. A chair is solid only if the design of the chair is good, the material is reasonably solid (which is determined by forms at lower level), and the chair is used in the right way (which means the forms at upper level). If the structure of a chair is not suitable, no matter how solid its wood beams are, it will crash. If a chair is made of tofu or cheese, no matter how perfect the design is, it will not hold its shape. Even a perfect chair cannot be abused. It follows that forms at each level are involved in causation. A chair made of material that is perfectly solid but with a poor design may still hold a reasonable weight. The forms on three adjacent levels are complementary to each other. What we get is the collective effect of them all. Form at macro level, or form at each level, plays a role in causation. Forms determine the pre-condition before the causation and define the result after the causation. Forms determine or define what kind of cause we have and what kind of effect we finally get. Forms are involved in causation. Without the form of a chair, a box of wood beams will not serve as a chair. Form directs the macro collective effect of the causation at micro level. Although the hierarchy as a whole is the totality of the reality, each level is one layer of the reality. When we describe the reality, or, when scientists formulate their theory, what one faces is not the hierarchy as a whole, but always one layer of the reality. Each level forms a domain for research and learning. Physicists, chemists, biologists, social workers, cabinetmakers, …they all have their own domain of reality. Correspondingly, there is only one causation as a whole. Causation perceived at each level is only one layer of the causation. However, it seems that physicists and chemists can always provide a self-complete causal explanation for their own levels, respectively. The reason is that, when they provide their theory, they always ignore the causation at other levels. For example, when a physicist proposes a theory, he usually pays attention only to the form at the levels for physics. He will ignore chemical reaction contained in physical change. Within physics, when he writes a law for free fall, friction from air is ignored or minimized by creating an ideal environment in his experiments. For the same reason, when a chemist writes an equation for chemical reaction, the effect from atomic change is not taken into account. Is there any causation across levels? Many philosophers believe that supervenience is a causal relation. Davidson is obviously one of them (Davidson 1980). Searle frequently says that the mental is “caused” by the physical. Kim (for him supervenience is a mereological relation) also talks about downward and upward causation (Kim 1999). What comments can we make from form realism? Since for form realism there is only one causation, causation at each level is only one layer of the causation. So the new question is, is there any causation between the two layers of reality at two adjacent levels? This is actually a new expression of the old question, is supervenience a causal relation? I mean to argue that supervenience is not a causal relation. An intuitive argument would be like this: it is awkward to say that a chair causes its arm to collide with the rim of a table. A more theoretical argument would run as the following. There are two notions of causation, perceived from macro perspective and micro perspective, respectively. Take a loaf of bread for example, from macro perspective we see bread as an individual. The good bread on Monday is the cause; the rotten bread on Friday is the effect. From micro perspective we see the causal interaction between atoms. The first notion is based on the fact that cause happens before effect, where cause and effect have different temporal locations. The second notion is based on the model of interaction, where cause and effect have different spatial locations. For a chair and its parts, there is neither temporal nor spatial difference. Therefore they cannot enter a causal relation. There is a causal relation between a chair and a table, where two objects have different spatial locations. We have argued that forms at each level are involved in causation. Causation, or one layer of causation, may exist at each level. We also argued that supervenience is not a causal relation, that is, we have cut any causal linkage between levels. The only option is that we have to go parallelism. That is, causation happens at each level where we can provide a conceivable causal account. It is amazing that we can provide conceivable causal accounts at several levels and thus get several chains of causation, and that they run parallel so well that we can formulate neat laws to describe them. The reason is that when a scientist of one discipline describes phenomena at his level, he ignores what is going on at other levels. 5. Epistemological Non-Reductionism What is the relation between scientific disciplines? Is there a reductive relation between concepts and theories of various disciplines like physics and chemistry? Humean idea atomism is a conceptual reductionism??? His idea may mean both concepts and propositions. The theoretical reductionists like Vienna Circle believe that all scientific theories can be derived from physics. With form realism in sight, this is obviously wrong. Scientists in different disciplines have their own layers of reality. Their major concerns are the forms at their own levels. Their theories are designed to describe forms at different levels. Naturally there is no reduction between theories of different disciplines. The solidness or solidity of a chair is determined by forms at three levels collectively. One cannot say that it is only determined by micro forms. The theory about macro forms is different from the theory about micro forms. We may say, all of our knowledge is knowledge about forms. We have to admit that the reductive approach, as a scientific method, is quite powerful some times. Some macro properties can be explained by micro forms. For examples, the color of a chair (or its wood beams) is a macro manifestation of a micro feature, which is determined by micro forms; the solidness of wood beams is also determined by the micro structure of wood cells. However, the macro properties determined by macro forms, such as the design of a chair, cannot be derived from the description of micro forms. Occasionally scientists may go deeper into an adjacent level for a better understanding of some macro properties and features. That is the practice in physical chemistry or chemical biology. The discovery of DNA is one fine example of this kind of cross-level work. The heredity as a macro feature can be partly explained by the molecular structure of DNA. However, the three laws of heredity (such as the 3:1 ratio between dominant phenotype and recessive phenotype) as the description of macro forms cannot be derived from the structure of DNA alone. Can we imagine an account of social change in terms of properties of chemical elements? Liu Chuang, in his discussion of phase transition as an emergent property in physics, makes a distinction between collective phenomena and cooperative phenomena, and argues that the property of collective phenomena can be reduced to the property of its parts whereas the property of cooperative phenomena cannot be reduced to property of its parts. Properties like color, temperature, pressure, and entropy are collective; properties like the design of a chair, the increase of entropy, and phase transitions are cooperative (Liu 1999, p93). Besides his mathematical demonstration, here is the philosophical explanation. For collective phenomena, the relation between its parts does not matter; for cooperative phenomena, the correlation (i.e., relation, structure, or forms) among its parts is real and substantial. It is a simple fact that the theoretical reduction and the unification of sciences proposed by Vienna Circle did not happen in the last 70 years. There is a principle of the Closure of the Physical, which says that the physical system forms a closed system. Physical theories should be able to provide a complete explanation of the physical system without recourse to the mental. Since this paper is not about the relation between the mental and the physical, the relation between the mental and the physical is different from the relation between two adjacent levels within the physical, I will leave this psycho-physical question alone in this paper and move our focus to another question. Within the physical world, there are multiple layers of reality. If each level is only a layer of the reality, what about the discipline at that level? Can we form a closed theory system for each layer? Is each level a closed system and each discipline a self-complete theory system? The answer could be positive, if based on certain conditions. For examples, a chemist can formulate his theory and write his equation of chemical reaction on the condition that the chemical elements will not break, that is, there is no atomic reaction; a cabinetmaker will do his design on a chair based on the condition that the timber is reasonably solid and his chair will be employed in a proper way; the Law of Free Fall in physics is true only on the condition that the friction from air is minimal and negligible. If the interference from adjacent levels manifests, no theory is self-complete. 6. Conclusion In this paper I have introduced the paper by Jonathan Schaffer, and tried to provide an argument for his third option, which is missing in his paper. With the admittance of the reality of form, we can treat each level as ontologically equal and grant full citizenship for each level in the republic of being. Then we proceed from ontological non-reduction to epistemological non-reduction and the problem of causation. Based on form realism, I argue that each level plays a role in causation. Based on ontological non-reduction, I argue that some macro properties can be fully explained by micro forms. The only remaining issue is the economical concern, that is, the violation of the principle of parsimony will lead to the unnecessary proliferation of the reality. As Schaffer points out, the economic concern is only a secondary concern. It should not be over-weighted. References: Schaffer, Jonathan, “Is There a Fundamental Level?”, NOǗS 37:3 (2003) 498-517. Aristotle, The Basic Works of Aristotle, ed. by Richard McKeon, Random House, Modern Library Paperback Edition, 2001. Davidson, Donald, “Mental Events”, in Essays on Actions and Events, Clarendon Press, Oxford, 1980. Kim, Jaegwon, "Supervenience As A Philosophical Concept", Supervenience and Mind, Cambridge University Press, Cambridge, UK, 1990. Kim, Jaegwon, Mind in a Physical World, The MIT Press, 1998. Kim, Jaegwon, “Making Sense of Emergence”, Philosophical Studies 95: 3-36, 1999. Liu, Chuang, “Explaining the Emergence of Cooperative Phenomena”, Philosophy of Science, 66(Proceedings) pp. 92-106, 1999. Oxford English Dictionary, Oxford University Press, Oxford, UK, 1989.