Reading Aristotle: Physics 1.9: Conclusion on the Principles

This is the final chapter in Book One of Aristotle’s Physics. In the previous chapter, Aristotle responded to the view of some earlier philosophers that change (generation and corruption) is impossible by making a distinction between what Aquinas would call “essential change” and “accidental change”. He begins this last chapter:

“Others, indeed, have apprehended the nature in question, but not adequately. In the first place they allow that a thing may come to be without qualification from not-being, accepting on this point the statement of Parmenides. Secondly, they think that if the substratum is one numerically, it must have also only a single potentiality–which is a very different thing” (Physics 1.9, 191b35-192a2) [1].

In chapter eight, Aristotle concluded that those philosophers who denied “coming to be and passing away and change generally” are mistaken because they did not grasp “this nature” of essential and accidental change. Here he seems to be saying that some other philosophers “apprehended” this nature, but “not adequately”. In particular, as Aquinas points out, these philosophers “touched upon” matter, or the potency of a thing. Continue reading

Souls and an Argument from Motion in Plato’s Phaedrus

If one reads through the dialogues of Plato, it won’t take long to realize that he is never short of arguments for the immortality of the soul. It seems to be one of his favorite topics to write about, and apparently he held the point as of utmost significance. A few months ago, I wrote a paper for school on three of these arguments in his Phaedo. But he also writes about it in the RepublicMeno, a bit in Timaeus, and, the one we’ll be looking at in this post, Phaedrus. In general, as an Aristotelian rather than a Platonist, I don’t tend to accept many of Plato’s arguments for the immortality of the soul (although I find them fascinating and profound), especially considering that Plato held the soul to not only exist after death, but also to have pre-existed our physical birth. Plato is, in many ways, a radical dualist, holding the human soul to be the true self and the body to be merely a prison thereof. I strongly disagree. But for now, my reason for looking at one of these arguments is not to discuss immortality.

I regard Aquinas’s “Argument from Motion” or First Way as perhaps the strongest argument for the existence of God that there is. But it’s certainly not an argument that St. Thomas just drew out of thin air; it had a long history of development. For the most part, this history can be traced to Aristotle, since he first presents the argument as really intended to show that there exists some ultimate being or cause behind the universe. While Aristotle’s version is certainly the first fully drawn out and “technical-ized” form of the argument, I think its general sentiment can be found earlier, namely in Plato. Although, as we’ll see, Plato doesn’t really seem to have used the argument as pointing to some cause of motion behind the universe; but I think his presentation thereof still has some interesting implications. Continue reading

Reading Aristotle: Physics 1.8: Essential and Accidental Change

In Physics 1.7, Aristotle determined the “number and nature” of the principles of nature. In chapter eight, the penultimate chapter of book one, he discusses the “error” of previous thinkers in denying the reality of change.

“We will no proceed to show that the difficulty of the early thinkers, as well as our own, is solved in this way alone. The first of those who studied science were misled in their search for the truth and the nature of things by their inexperience, which as it were thrust them into another path. So they say that none of the things that are either comes to be or passes out of existence, because what comes to be must do so either from what is or from what is not, both of which are impossible. For what is cannot come to be (because it is already), and from what is not nothing could have come to be (because something must be present as a substratum). So too they exaggerated the consequence of this, and went so far as to deny even the existence of a plurality of things, maintaining that only Being itself is. Such then was their opinion, and such the reason for its adoption” (Physics 1.8, 191a23-33) [1]

I find the history of philosophical/intellectual development fascinating, almost as fascinating as the philosophical content on its own. The emergence of early Greek philosophy is quite unprecedented in history, and unsurpassable in its significance and influence. The early Greek philosophers were attempting to understand the natural world in which they found themselves, and they were doing so by searching for the “principles” of nature, the explanation of why things were/happened the way they did. This led some of them to adopt quite radical positions. Aristotle, throughout much of the Physics and the rest of his works, takes a sharp and definitive stand of disagreement against these prior philosophers, but here he at least admits a sympathetic understanding of how they went astray. They were, he suggests, “misled . . . by their inexperience”, which is not surprising, considering that they were literally the trail blazers of all western science and philosophy. But, whether or not their error is understandable or not, it still remains error, and it is to this that Aristotle offers his response. Continue reading

Reading Aristotle: Physics 1.7: The Principles of Nature

In Physics 1.6, Aristotle established that the number of fundamental principles of nature must be three. He begins 1.7:

“We will now give our own account, approaching the question first with reference to becoming in its widest sense: for we shall be following the natural order of inquiry if we speak first of common characteristics, and then investigate the characteristics of special cases” (Physics 1.7, 189b30-32) [1].

Since he is searching for the underlying principles of nature, and since “nature” itself to Aristotle is the principle of motion of things–“a source or cause of being moved and of being at rest in that to which it belongs primarily” (2.1, 192b22-23) [2]–then to understand the underlying principles themselves we must examine the motion of things. And so here he states that he will consider “becoming in its widest sense”, as it applies to all things commonly, before then investigating individual cases. Continue reading

Beginning Metaphysics: First Philosophy as ‘Lord of the Sciences’


“The least initial deviation from the truth is multiplied later a thousandfold” [1] wrote Aristotle in his De Caelo. It is to this that St. Thomas refers when he begins his own brilliant metaphysical treatise, De Ente et Essentia, by stating: “A small mistake in the beginning is a big one in the end” [2]. His point is that we must start our metaphysical inquiry from the right place (which for him means noting the distinction between essence and existence) or else we will go awfully awry by the time we reach the end. But on an even broader level, we might say that we must begin all rational inquiry with a solid metaphysical foundation, or else our entire understanding of reality will be, ultimately, completely skewed and fundamentally flawed. So despite the fact that the word “meta-physics” literally means after physics, Aristotle was right all along when he originally named it “first philosophy”, to which physics is “second”, with all other sciences proceeding therefrom. Continue reading

Reading Aristotle: Physics 1.6: The Number of Principles

In chapter 5 of his Physics, Aristotle established that the fundamental, underlying principles of natures must be “contraries”. In 1.6, he asks how many are the underlying principles.

“The next question is whether the principles are two or three or more in number. One they cannot be, for there cannot be one contrary. Nor can they be innumerable, because, if so, Being will not be knowable: and in any one genus there is only one contrariety, and substance is one genus: also a finite number is sufficient, and a finite number, such as the principles of Empedocles, is better than an infinite multitude; for Empedocles professes to obtain from his principles all that Anaxagoras obtains from his innumerable principles. Lastly, some contraries are more primary than others, and some arise from others–for example sweet and bitter, white and black–whereas the principles must always remain principles. This will suffice to show that the principles are neither one nor innumerable” (Physics 1.6, 189a11-21) [1].

So the Philosopher rules out from the start the possibility of the principles of nature being only one in number. This is because he has already shown that the principles must be contraries, but “there cannot be one contrary”. Obviously, a “contrary” must be of something. Hot and cold are contraries, but if just cold existed, then it could not be called a “contrary”, since it would not be contrary to anything. As Aquinas succinctly puts it in his commentary, “nothing is the contrary of itself” (Lectio 11.83) [2]. Aristotle also rules out the possibility of the principles being “innumerable” or infinite in number, giving four brief reasons for this conclusion: First “Because, if so, Being will not be knowable.” If the principles are innumerable, then by definition they cannot be known, and this would render being intelligible. Continue reading

Epicurean Cosmological Argument

Over at the ex-apologist blog, another highly respected online advocate for naturalism/atheism has posted a very interesting argument which is much more up my alley than some of the more contemporary type arguments I’ve been responding to (although Mr. Lowder also has an argument which is related to this present one that we’ll look at within a few weeks or so). The ex-apologist labels the argument an “Epicurean Cosmological Argument for Matter’s Necessity”, and it acts as a kind of metaphysical counter argument to some of the theistic cosmological arguments, including Aquinas’s first three Ways, which I’ve written about on this blog.

The basic argument goes like this:

“One can find, through the writings of Lucretius, a powerful yet simple Epicurean argument for matter’s (factual or metaphysical) necessity. In simplest terms, the argument is that since matter exists, and since nothing can come from nothing, matter is eternal and uncreated, and is therefore at least a factually necessary being” [1].

This argument, apart from being interesting in its own right, is actually pretty significant, in that the materialism (atomism) of ancient philosophers such as Epicurus is one of the main adversaries to the Platonic/Aristotelian transcendental worldviews adopted by and implicit within classical theism. And, unlike some of the more contemporary arguments I’ve been examining recently, this argument gets down into the very fundamental nature of reality. Continue reading