Rabbi Slifkin once wrote:
Any intelligent discussion concerning Rambam's philosophy and its applicability today has to take into account the fact that Rambam was countering Aristotelianism, and modern science does not fit into his categories. Back then, the options were either that the entire universe and everything in it were created meta-naturally, or that everything always existed as it does today. Ultimately what Rambam was fighting against, and what he defined his ikkarim based upon, was the Aristotelian model. There was no idea of explaining that the universe was created meta-naturally but that things in it developed according to laws of nature, since there was no theory of laws of nature that could explain this. So it's problematic to be medayek in Rambam's words regarding whether such an approach is kosher or not. And whether this is closer to the Aristotelian model or to Rambam's model can be debated.
This, in my humble opinion, is a serious misunderstanding of the Moreh Nevuchim. The Rambam tells us not only that Aristotle's position contradicts our mesorah, but he also tells us what the mesorah actually is:
MN 2:17 (see http://press.tau.ac.il/perplexed/chapters/chap_2_17.htm, note 6, for a compilation of translations of this passage.)
For we, the community following in the footsteps of Moshe Rabbeynu and Avraham Avinu, aleihem hashalom, believe that the world came into being in such-and-such a form, and became such-and-such from such-and-such (haya kach mi-kach), and such was created after such.
What specific, existing Jewish belief of things coming onto being (in full form—as the Rambam explains in Moreh Nevuchim 2:30, where he also says that all was created simultaneously, and then one-by-one "set apart") should we suppose he was referring to, when writing of things becoming "such-and-such from such-and-such"? To my mind, it is clear that he meant that part of the belief the Jewish community received from Moshe Rabbeynu is the meta-natural formation of, say, Adam from the adamah, and not from the beheima.
The Rambam (ibid.) immediately continues:
And Aristotle would attempt to topple our words, and would bring against us evidence from the nature of the set, actualized, complete metsius as it acts regularly. But we concede to him that once it was established and reached completeness, it was not one iota similar to what it was at the time of its being generated, and that it was brought into existence after being absolutely absent. What argument in all he says holds up against us? These arguments are indeed compelling against one who claims that the fact that the world’s being mechudash can be proven by the way the world is now, in its permanent nature. But I already let you know that I am not saying this.
The Rambam was not looking for a way to explain how a meta-naturally created world was developed, only resorting to a meta-natural explanation because “there was no idea of explaining that the universe was created meta-naturally but that things in it developed according to laws of nature, since there was no theory of laws of nature that could explain this.” No; the Rambam was presenting the mesorah, which clearly reports that besides the initial creation ex nihilo, there was a maaseh breishis, the further extraction, fashioning and positioning of the world’s components into their mature state; and it is this process to which our refraining from melacha every seventh day testifies. (See Rav Shamshon Raphael Hirsch’s piece in his Chumash commentary, where he emphasizes that the fact that the post-maaseh breishis world does not possess the properties to again produce the another world such as ours is the proof that there was a maaseh breishis, and that this is what our refraining from melacha on Shabbos testifies to.) And this is why the focus in the pesukim is not on the creation ex nihilo component, but on the mesorah that “sheyshess yamim assah Hashem ess hashamayyim v’ess ha’aretz.”
Most certainly, the Rambam does not choose to reinterpret or distort the mesorah on the grounds that some other explanation seems "more elegant" to his mind. For such arrogant grounds have no relevance to the G-d-given mesorah that it was otherwise.
Of course the Rambam was directly addressing Aristotle's idea of a universe without a beginning. That was the contra-mesorah idea in vogue then, and the Rambam spoke about why it’s important the mesorah teaches us that Aristotle’s is not the way the world came into being.
(And yes, just as the Kuzari, the Rambam reluctantly admitted that Plato’s version escapes the logic-based criticism he designed; and, similar to the Kuzari, he reluctantly admitted that if Plato’s version were absolutely proven, we would have to reinterpret the mesorah so that matter always existed eternally with Hashem[--but note that unlike Aristotle, Plato allows for meta-natural formation of matter into actualities non-existing beforehand, and allows maintaining the 6-day meta-natural process of creation as described by the pesukim]; and if Aristotle’s theory were absolutle proven, we would have to abandon the mesorah altogether, chas v’shalom. He also says that this can never happen. His reason for this applies to accepting evolutionary theory as well.)
But what is important is that the Rambam as well as all our baalei mesorah would consider either move to be a major, radical departure from the mesorah as it had been understood since the days of Avraham Avinu and Moshe Rabbeynu. It would mean that until his time, Hashem allowed and fostered, through narrative and commandment, a false idea of a fundamental teaching of the Torah. And no rishon ever suggested this beyond the hypothetical.
And again, what is most important is that Rambam tells us what the Jewish belief about the world's initial development is. He does not need to specifically reject every possible alternative that deniers of the mesorah may ever conceive. To think he did is as unreasonable as saying that by emphasizing that Hashem is one, he was only rejecting dualism, past Greek polytheism and vogue trinity, but had he known of a religion of specifically four gods, or one God of Evil, he may have reconsidered.
Besides, several Greek philosophers did teach forms of evolutionary development as explanations of the world's present condition (www.iep.utm.edu/e/evolutio.htm) --and you can be sure they also had their theories of laws of nature to "explain" their fantasies.* The Rambam could easily have slapped together some rendition of their evolutionary story of natural forces producing our world with the proviso that there was first an initial Creation, just as Rabbi Slifkin does. The Rambam didn't, and even if it were in vogue would not have. He did not need to specify that such an idea is incompatible with the mesorah, because he held that:
"we, the community following the footsteps of Moshe Rabbeynu and Avraham Avinu, aleihem hashalom, believe that the world came into being in such-and-such a form, and became such-and-such from such-and-such, and such was created after such."
*Evolution is not so much a modern discovery as some of its advocates would have us believe. It made its appearance early in Greek philosophy, and maintained its position, more or less, with the most diverse modifications, and was frequently confused with the idea of emanation, until the close of ancient thought. The Greeks had, it is true, no term exactly equivalent to "evolution"; but when Thales asserts that all things originated [naturally--ZL] from water; when Anaximenes calls air the principle of all things, regarding the subsequent process as a thinning or thickening, they must have considered individual beings and the phenomenal world as, a result of [natural--ZL] evolution, even if they did not carry the process out in detail. Anaximander is often regarded as a precursor of the modern theory of development. He deduces living beings, in a [natural--ZL] gradual development, from moisture under the influence of warmth, and suggests the view that men originated from animals of another sort, since if they had come into existence as human beings, needing fostering care for a long time, they would not have been able to maintain their existence. In Empedocles, as in Epicurus and Lucretius, who follow in His footsteps, there are rudimentary suggestions of the Darwinian theory in its broader sense; and here too, as with Darwin, the mechanical principle comes in; the process is adapted to a certain end by a sort of natural selection, without regarding nature as deliberately forming its results for these ends.