[MUSIC] Now, you probably won't be surprised to learn that Parmenides' arguments did not bring naturalist inquiry to a halt. Scientific thinkers went on formulating hypotheses about the changing cosmos, in spite of Parmenides' arguments that change is an incoherent notion. But we have good evidence that many of these later thinkers were keenly aware of Parmenides' challenge, and that they took care to formulate their own view in a way that tried to avoid Paremenides' objections. We will conclude our discussion of the Presocratics, by investigating the responses to Parmenides in the work of Empedocles, Anaxagoras, and the atomists, Leucippus and Democritus. Let's start with the poet philosopher Empedocles, who develops an elaborate cosmology, but is also keenly aware of Parmenides injunction. In fragment B11, he calls fools those who quote, expect that there comes to be what previously was not, or that anything perishes and is completely destroyed. He here endorses Parmenides' conclusion that there is no coming into being, and no perishing as each of these involves what is not, either at the beginning, or at the end of the change. Now on the same theme, Empedocles writes in fragment B12, for it is impossible to come to be from what in no way is, and it is not to be accomplished and is unheard of that what is perishes absolutely. Now, it's worth pausing over the adverbs here. Empedocles does not just say there is no coming into being from what is not, but from what in no way is. And similarly, what he rejects is not simply perishing, but perishing absolutely. What is the force of these qualifications? Is there a difference between what in no way is? And what is not, but only in a way? Now you might think that the answer is no. Is, and is not, are exclusive and exhaustive alternatives. But in fact there are two very different ways we use is and the verb to be quite generally. One way is to invoke existence. As when I say there is no Lochness monster, or I wonder is there life on Mars? The other way to use is, and to be, is the is of predication. When I say roses are red, I'm using the verb to be to link a subject, roses, with a predicate, red. It is one thing to say that roses exist. There are roses. And another thing to say that they are red. But we use the same verb, the verb to be in both cases. In this case, in the plural, are. So now, suppose that when Empedocles writes about what in no way is, he is using is in the existential sense. What in no way is, is something that does not exist. We can concede to Parmenides that there's a real problem with thinking about that sort of thing, since there exists no thing for our thought to be about. But what about something that is not, in a less drastic sense? Here is where the predicative sense of is not, comes in handy. Because something that is not in this sense, can still be something that is, in the existential sense. Take for example our red rose. There it is. It exists, but it is not yellow. Still, in spite of its being not yellow, there isn't any problem in thinking about it since it still exists. The moral of the story is that the Parmenidean problem about thinking about what is not, is only a problem for what is not in the existential sense. So, if change involves what is not only in the predicative of sense, then it is not vulnerable to the Parmenidean objection. Let's apply this to an example. Suppose an apple turns red as it ripens. Previously it was not red, and now it is red. So we have a case of coming into being from what is not. But what is not in this initial condition, is an apple, which although it is not red, it still is, it exists. And so it is a perfectly acceptable object of thought. So even though the apple's turning red is in a way a case of coming to be from what is not, there is nothing problematic about it from a Parmenidean point of view. Now the apple turning red would be problematic for Parmenides, if all we could say about it was, now there is a red apple, but previously there was not. That makes it sounds like a red apple popped into existence, ex nihilo, that's Latin for, from nothing. But that isn't all we can say about this change. We can truly say that there was something there at the beginning of the change, the apple. And that it changes from green to red. So no creation ex nihilo. Okay, that's the general gist of Empedocles' response to Parmenides. In the next lecture we'll look more precisely at how all these distinctions can be deployed in a precise criticism of Parmenides' argument. And then we'll consider Anaxagoras, Leucippus, and Democritus, and see that for all their differences with Empedocles on the details of their cosmological theories, they agree with him in the general shape of their response to Parmenides.