Thursday, July 18, 2013

On potentiality and actuality

Hurlbut writes this:- These are well defined by Aristotle. His purpose was to respond to Parmenides and Zeno at the Eleatic school, who claimed that change does not occur. They claimed that there is only being, and non-being, and being cannot come from non-being, and being already is, and so therefore nothing ever changes. But Aristotle thought this was wrong, and tried to work out why it was. His answer is that there is a sort of middle-ground between being and non-being: potentiality. Take a glass of water on your table. It is actually on the table, but potentially spilled on the floor, potentially drunk, potentially evaporated, and so on. It has the capacity to change, and this capacity for a future state is called potentiality, by Aristotle. >the total sum of energy in the universe, even if it is finite, is sufficient to describe all instances of potentiality coming to actuality There is a lot more to the Aristotelian position. The act/potency distinction applies in various other ways. For example, it also applies in the distinction between essence and existence. The essence of a Phoenix and its actual existence are distinct, in that knowing the one (what it is to be a Phoenix) does not tell you the other (whether such things actually exist). So the sum total of energy in the universe is still not enough to describe all potentials becoming actual, because the essence of energy is distinct from its existence. Simply knowing what energy is will not tell you if energy exists. In other words, energy actually exists, but potentially does not. And per the second premise something else must actualize the potential existence of energy. >what Aquinas would call a particle's "potentiality" could be described as an intrinsic property of the particle And if so, then you are agreeing with the Aristotelian-Thomistic position! One of the most important concepts in Aristotelian metaphysics is that of final causality: an intrinsic property of an object to do X rather than Y. If it is just in the nature of virtual particles to pop into existence out of the quantum vacuum, then that is saying that they have a final cause. And so they have a potential towards a certain end (popping into existence), and you have the act/potency distinction. >if God is pure actuality, God cannot do anything. All concepts we use to describe action – causality, creation, etc. – imply the existence of a potential change. Pure actuality would be non-temporal, because being temporal means having the potential to get older than one was. Being non-temporal, pure actuality has already done everything, from its perspective. Everything is one timeless now, and we simply move through time "tripping" over its actions as we go. Actions which are already in place. >He exists as this abstract "actuality" that exists at all possible points in time, and any changes are only changes from the perspective of observers such as ourselves (ironically enough, this is actually similar to the concept of the "block universe"). That's exactly right! >It's interesting to note that this is precisely what happens in quantum mechanics! The wave function of a particle can only be determined by probability; there is no classical mechanism that can explain why the particle changes at one time rather than another. But remember the essence/existence distinction (which aligns with potential/actual, respectively). A merely potential object does not exist, and so cannot cause anything, including bringing itself into existence. Consider a quantum particle that, by its very nature, spontaneously decays. What makes it the case that such an object actually exists, rather than just potentially? Certainly not itself, as it would then have to exist in order to make itself exist. It would have to simultaneously exist and not exist. >Time flows in arbitrary directions, and no specific point can be said to be the "beginning" or "end". This is the common misunderstanding: that Aquinas is trying to argue that the universe must have had a beginning at some point. Nothing could be further from the truth. Aquinas was well-aware of the Kalam Cosmological Argument, and rejected it. He doesn't think an infinite past is an actual infinite: Aquinas is arguing for a current, sustaining cause, no matter how old the universe is, even if it is infinitely old. I like to explain it by using the concept of a receiver and a giver. If there is a receiver, then necessarily there is a giver. If the frozen lake is being actualized by the cold air, and the cold air is being actualized by the jet stream, and the jet stream is being actualized by the sun, and the sun is being actualized by its nuclear reactions, then all these are receivers, and the only possible way the chain can terminate is in an unactualized actualizer. It could not possibly terminate in an actualized actualizer, because then it just wouldn't be the termination point. The ultimate explanation of the lake's being frozen. So you see, it has nothing to do with the origin of the universe. >relies upon the fallacious idea that empirically observed phenomena can be taken as axioms that apply in all conceivable circumstances The argument is not relying upon empirically observed phenomena. It starts with the anti-Eleatic position: change occurs. It argues that if change does not occur, then change definitely still occurs on the level of your own consciousness, as you reason from premise to conclusion. But this is then incoherent, because your consciousness is a part of nature and so you would be saying that change occurs and does not occur. The second premise is argued to be logically certain as well, because a potential (non-existent) object cannot cause anything, because then it would have to exist and not exist simultaneously. And the third premise is argued to be logically certain as well: as long as something is receiving, something must be doing the giving. ............................................................................................................................. There's a 10 course meal, right there, hey? Gonna have to break this down a bit to criticize it, but for now, just soak in the ambience, if you can do that without barfing!

1 comment:

pboyfloyd said...

Hmm, yea, all the formatting disappeared.