Understanding Mental causation in the Enlightenment of Top-down Causation within the Physical

Ziyi Sang


Physics is traditionally described by bottom-up evolution, an evolution where the lower levels of complexity determine the higher levels of complexity so that a system is equal to the sum of its parts. However, this traditional physics view can no longer explain everything we witness today such as consciousness or fractional quantum hall effects. As recent arguments suggest that top-down causation is not only consistent with elementary physics but also necessary to be taken into consideration when analyzing a physical system. On the other hand, the concept of Top-down causation is closely related to the topic of mental causation in philosophy of mind, where the mental is the higher level (the Top) and the physical is the lower level (the down). Such a topic is concerned with the problem of free will and the nature of consciousness. Hence, our project will examine Top-down causation with a fuller consideration from both the physics and philosophy perspectives. Though the problem of mental (to physical) causation is more complex than the problem of Top-down causation within the physical, the analysis of the latter, in fact, points out the right way to deal with the former.

We will first introduce the basic concept of Top-down causation based on Ellis's, Anderson's and Laughlin's accounts in Chapter 1. In Chapter 2, we will consider List & Menzies' reply to the objection of Kim's exclusion principles. During the process we will introduce the ideas of reductionism, supervenience, multiple realizations and proportional causation. In Chapter 3, we will demonstrate Top-down causation by applying the introduced concepts to several physical systems. In Chapter 4, we introduce Davidson's Anomalous monism as an alternative view to the account of Top-down causation provided previously. In anomalous monism, description of an event is treated separately from the state of affairs itself. Our comments on Davidson's account also demands the necessity the mental description, which is answered in Chapter 6. In Chapter 5, by distinguishing causal explanation and causation, we reveal that "levels" of complexity and "proportional causation", though reflecting certain causal processes and dependency within the system truthfully, are descriptive-dependent, and hence should be treated as an intentional explanation rather than an extensional cau- sation. Meanwhile, Anomalous monism should be taken into consideration when analyzing Top-down causation. In Chapter 6, we reveal the structure of the system itself is what makes the description of mental phenomena necessarily and possibly true. This structure comes from the "constitutive relation" between the constituents (the down – the lower level) and the whole (the top – the higher level), and reflected through the description based on our perception. Top-down causation is therefore not a genuine causal relation but a constitutive relation. However, the denial of top-down causation does not weakened mental causation, for the constitutive relation guarantees the causal efficacy of the mental. In the end, we introduce the appropriate account of Top-down causation/constitutive relation by renewing the concepts of "levels" and "causation" considered in the previous Ellis and List & Menzies accounts.