Physicalism is true.

Ave The Existence of Physical Entities Imagine that you are taking a walk around an urban city. As you walk, you will hear the loudness of the cars speeding past you. Being a large city, you may also hear the wailing, high-pitched frequency of an emergency vehicle. It is undeniable that your conscious experience includes the experience of hearing these sounds. What causes us to hear loudness and pitch the way that we do? What factors mold the structures of our conscious experience? According to physics, our subjective experience of loudness relates to a physical quantity called the intensity level, which depends on the intensity of the sound and the intensity of some reference level. Furthermore, our experience of pitch depends on the frequency (cycles per second) of the sound wave. A higher frequency will lead us to hear a higher pitch, and a lower frequency will lead us to hear a lower pitch. According to this picture, our conscious experience of the world around us depends on physical quantities, entities, and relationships, Therefore, the mere existence of conscious experience implies the existence of physical entities as well. The picture that I just described relates aspects of our conscious experience to physical quantities. Now we can mention a different picture, one in which all of reality is mentally constructed and the physical does not actually exist. Unfortunately for the idealist, this picture must be incorrect. To produce a sound that is experienced as being twice as loud requires a sound wave with ten times the intensity. If idealism is true, one would expect a direct relationship between these two quantities. Namely, there is a mental concept “sounding loud” that remains constant until ten times the intensity has been reached. Everything that is true of one’s conscious experience remains the same, yet something else, the intensity of the sound wave, is changing. The mental aspect of our experience has not changed, as nobody ever walks down a street and notices that the sound they are hearing has increased in intensity by 2.5 (for example). Since there is a change, and this change has been ruled out as being a change in the mental aspect of the scenario, there must be a change to something non-mental. Therefore, the non-mental must exist. Physical facts fix all of the facts (supervenience) Facts are, in essence, true propositions. Analytic philosophers concern themselves with what propositions are meaningful and what propositions are not. In order for a proposition to be meaningful, and therefore capable of being true or false, a proposition must be free of lexical, structural, and other forms of ambiguity. One of the crowning achievements of the hard sciences is its analytical and quantitative precision that is free from such ambiguity. The set of concepts invoked by fields such as chemistry and physics in order to explain observed phenomena use mathematics to obtain this analytical and quantitative precision. For this reason, if one is to have access to the facts about reality, one must do it through a conceptual schema that is analytical and quantitative. The hard sciences, considering their analytical and quantitative nature, as well as their stunning predictive power, are therefore the conceptual schema from which we should investigate the nature of reality. Although other subjects may be interesting from an intellectual standpoint, we must accept the primacy of the hard sciences in investigating reality. Anything which is inconsistent with the hard sciences is by implication inconsistent with the basic conceptual schema for investigating reality, and is therefore unacceptable. Having established the primacy of the hard sciences in investigating reality, it is now necessary to explicate the ontology offered by these hard sciences. Practically speaking, chemistry and physics investigate the same topics, so by convention, I will simply describe the ontology given to us by modern physics. The standard model of particle physics, which has been found to be supported by empirical evidence (the discover of the Higgs boson was such an experiment), tells us that the fundamental constituents of reality are fermions and bosons. For this reason, the standard model of particle physics is inconsistent with any notion of non-physical entities. Earlier, I established that if there is a contradiction between the hard sciences and any other subject, notion, or proposition, we must choose the hard sciences. Now, given that the standard model of particle physics is inconsistent with the notion of non-physical entities, we must rule out the existence of non-physical entities from our view of reality. Therefore, all actually existing entities are physical. It has been established that all actually existing entities are physical. Considering that physicalism amounts to the assertion that all actually existing entities are supervenient on the physical, I only have to prove that physical entities are supervenient on the physical in order to prove that physicalism is true. Remember that supervenience is a relationship where the lower-level properties of a system determine the higher-level properties of a system. This means that I must prove that given a physical entity, E, a change in the lower-level properties (B) entails a change in the higher-level properties (A). The hard sciences make this trivially easy to demonstrate. As an easily understood example, chemistry explains how lighting a match involves changes in lower-level properties (i.e. a chemical reaction) that determine the higher-level properties of the match (it is now on fire). Physical entities are supervenient on the physical. Therefore, all actually existing entities are supervenient on the physical. This means that physicalism is true. As I have more room to type, I will spend characters addressing some possible misconceptions that may arise. I am not affirming the position that science is the only source of truth and knowledge. There are other subjects, such as mathematics, logic, and philosophy that can reach similar levels of precision and clarity. Rather, for my argument to work, I only need to defend the assertion that if a notion is inconsistent with the hard sciences, then we should choose the hard sciences as being the correct option. Usually, there is a significant degree of interplay between science and mathematics, with vector addition from physics demonstrating the mathematical law of the commutative property, and physics utilizing math as its "language". For this reason, I view them both as analytical and quantitative fields that reinforce each other rather than two fields fighting for supremacy over our investigations into reality. Furthermore, it is worth clarifying that my denial of the existence of non-physical entities does not in any way entail the denial of the existence of mind. Physicalists can speak of concepts like "mind" as coherent as a dualist will. As Shelly Kagan states in his book Death, physicalists simply contend that the mind is something that the body does. The commonly held belief that physicalists cannot coherently speak about a mind is a misunderstanding of physicalism. Facts, expressed as propositions, must be analytical and precise, and therefore, only analytical and precise fields have any true knowledge about the nature of reality. The hard sciences, although they are not the only fields consistent with this description, take primacy due to their stunning predictive power. However, the hard sciences describe a physical universe of purely physical interactions, leaving out any mention of non-physical entities. Therefore, non-physical entities do not exist due to their inconsistency with the hard sciences, which take primacy over all other sources of knowledge. Since only physical entities exist, all that remains is to use basic science to demonstrate that these physical entities are supervenient on the physical. Once this is done, the truth of physicalism has been established. Although physicalists still have to decide between rivaling interpretations, it remains the only plausible ontology. Thanks for reading. Vale References Physics: Principles with Applications http://online.sfsu.edu... The Atheist's Guide to Reality