I'm glad to see that I've driven some traffic Anthony's way, and that there's a busy little debate going on there. You can find the link on my previous post, where other's already have. I haven't seen a word there yet about the history of science, and I think this is the massive elephant in the room. That is, the furtherance of Science very depends upon a degree of fabrication that doesn't exist prior to the discovery of this or that.
A very simple example? Galileo's conception of the heavens depends upon the development of the telescope by Hans Lippershey in 1608. It must be understood that Lippershey's telescope was not the first attempt of the device, but the first success. If I incorporate the existence of magic, the telescope comes into being as soon as the telescope is conceived ... ie., prior to 1608. We have evidence of 'reading stones' being employed as early as the 12th century. Magic, it is fair to say, would have enabled the invention of the telescope nearly five centuries before Galileo ... which presumes also the invention of spectacles before the 15th century, superior investigations into optics long before Newton, the destruction of the Catholic/Ptolemy earth-centered universe before Copernicus would have had a chance to write his textbooks, etc., etc.
This sort of example can be applied to every science. Magic would, across the board, change the events of history and the distribution of ordinary technologies in literally thousands of ways. A simple cantrip replaces Louis Pasteur long before the 19th century; healing spells enable medical surgery on the body long, long before the development of anesthetics and Lister's antiseptics; divination spells clarify early on the existence of guessed-at concepts like air pressure, electricity, atomic structure and the existence of gasses; metal and stone transformative and creation spells allow greater superior mechanical engines, alloys and tools; resurrection spells enable explanations for fossil discoveries; mind control spells increase the likely success of early examinations into anthropology and psychology ... there really is no end.
It is the height of absolute stupidity to claim in any way that the existence of magic would not speed the progress of technology, and therefore the understanding of the universe through experimentation and conclusion (which is science, after all), far beyond our present condition.
And so, to avoid sounding like a complete moron, the argument is almost always, "People would lose interest in science if magic existed."
Bullflops. Utter, unmitigated bullflops.
In the world of magic as presented in D&D (and I don't give a fuck about arguments that there's some flaw in D&D magic that somehow ruins or wrecks the game - more bullflop, that), human beings are still human beings. Hearts still pump blood, hands still hold weapons in the same way, the mind retains its human characteristics and we are still born, fall in love, give birth to children, grow old and die. As such, the fundamental problems of the denizens in a D&D world are the same problems that exist in this non-magical environment. We must clothe ourselves, we must find shelter, we must feed ourselves and we seek comfort. We continue, as a creature, to succeed in accomplishing these things through experimentation. We continue to fashion tools. We continue to seek a means, and therefore knowledge, about how to fashion better tools. While it may be true that magic will succeed in fashioning some tools for us, magic must be advanced in the same manner as any other technology. New magical methods do not come into existence spontaneously. They must be proposed; they must be developed and tested and they must meet certain criteria in order to be useful. Magic, like science, requires a fertile mind. And fertile minds are encouraged by need, not abundance.
Magic or science, we would still be the same creative creatures we are now. The fact that we would be solving problems this way - with magic - would not change our habits in solving problems in any other way. Let's have it clear that not everyone is able to DO magic ... are people without the necessary wisdom and intelligence supposed to sit around in caves? And are we to assume that just because people with intelligence were capable of doing magic, they automatically would? Ridiculous. I'm not an engineer now, am I? I refer to the flagrantly stupid argument - that I've heard before, but not with regards to Anthony's site - that people would be compelled do to magic and therefore would not investigate science. Oh my god that is a fucking dumbass thing to argue! Just pile up all the parents in the world who want their children to blindly follow in their own religion and see how high a mountain you build. People can no more force their children to obediently follow the rules than they can force themselves to cease their own stupid assumptions. Children will grow up and do whatever they please ... it has been true in every era. It will always be true.
I feel a need to redress the argument from two paragraphs prior by suggesting the gentle reader get off his or her ass and read the short story Olympics by Isaac Asimov. I should have said so before.
The reality is that magic and science would progress in tandem, just as religion and science progress. One might as well argue that the existence of science precludes the existence of art, or that the existence of religion precludes the existence of hedonism. Human beings are plentiful and spectacularly varied. There is room enough in the world for every kind of behavior. Practitioners of magic, no matter how many of them there were, would not stop the observation of natural phenomenon. I have not heard anyone suggest that invention would become impossible. How then would it become obsolete?
Now, there was one point that richard at Anthony's site touched upon (richard is one of those heightened souls who has explained that I am undeserving of his comments), which was the research of magic. And there lies an important, and rarely pursued question. If magic exists, when is it discovered? I have sat and written numerous posts about the development of technology - which technology inspires the first sentient creature to have the first flash of inspiration that enables the onset of magic? When does this occur? Before Christ? Before the Romans? Before Ramses and the supposed freeing of the Jews? Before Abraham? Precisely when does this occur?
And if this is your world, and the history is one of your own making, how long has magic been in existence? And how long has it existed at the level it is at now? Has fireball existed since the very beginning? Was every spell invented at approximately the same time? Or has it been only fifty years or so that the really powerful spells have come into continuous use? Remember, we live in an age where change and development has been mindboggling. Could not magic have come into existence only fifty, perhaps seventy years ago, like computers ... and could not spells have been developed like the Internet, only to become widespread only 12 or 14 years ago?
Food for thought. I will consider, and perhaps write further on this tomorrow.