That being said, I see a popular trend emerging in some parts of the Jewish world today which are deeply concerning. Maimonides and select other great Jewish scholars in our past are being used or invoked as role models for "open inquiry", "rationalist approaches", and even the wholesale "modernization of Judaism". Those who invoke the Maimonides and the Guide for the Perplexed as just such a permission, should remind themselves of the fact that at least some amount of empirical query into the deeper nature of our universe is clearly forbidden by the Torah itself as well as the tradition.
The Talmud in Chagiga talks about the prohibition of exploring "mah lifnim umah leachor" (what is beyond us). The Talmud in Sanhedrin prohibits reading "sefarim chitzonim" (foreign works). The medieval sages there translate this to mean learning the works of Aristotle and his friends. The Talmud in Berachos forbids teaching "Chochmas Yevanis" (Greek Wisdom).
Maimonides himself in "Hilchos Avodas kochavim" chapter 2 halacha 3 (Laws Concerning Idolatry) says that the prohibition of "Lo Sassuru" (the Torah prohibition against following the desires of ones heart and eyes) prohibits a person from exploring through open inquiry any topic that may take a person away or cause them to doubt or question any fundamental precept of our faith.
This is so deeply rooted in Jewish law that even the medieval sages themselves felt it necessary to bring Maimonides and others like him to task for having gone "against" these prohibitions.
The main justification that others offered for Maimonides is that it was a time of crisis for the Jewish people who were being pulled into the seductive ideas of the day. He was someone who had completely mastered all areas of Torah and could handle approaching philosophy without considerable danger. Furthermore, the Rivash then tacks on at the end of his responsa about Maimonides that "and even still he was led astray in certain things" and "therefore we should make a "kal vechomer" (a fortiori logical inference) about ourselves in this matter".
Others (see igros kodesh for the Lubavitcher rebbe) have clearly pointed out that there are blatant contradictions between what Maimonides wrote and codified as Jewish law in his Mishneh Torah and what he wrote in the guide for the perplexed. There are numerous examples of these contradictions and they are startling in their import. This inconsistency has forced many great scholars to suggest that the guide for the perplexed was deliberately "stretching" the possible understandings of the Torah to their outward limits in order to appeal to those Jews who had lost their way. That's hardly something that can be pointed to as a text calling for modernization. If anything the modern minded person should feel a little cheapened by the notion behind the Guide for the Perplexed since at least one way of looking at it was that it was somewhat in-genuine in its motivation.
So whereas many scholars who followed Maimonides accept the underlying legitimacy of such an undertaking as the Guide for the Perplexed, that still comes with terms and conditions, red flags, and cautionary notes for the rest of us. One also can not simply slough off these critiques of the later scholars by saying "how could they know what Maimonides intended? This is true because Maimonides himself codified as law in Mishneh Torah the prohibition of doing precisely what he then did in the Guide. He also clearly leaves serious internal contradictions between what he wrote in Mishneh Torah and the Guide and it is quite clear that he did not mean to retract what he wrote in Mishneh Torah. In as much as this is the case it is implicit in Maimonides own methods that one or both of the above suggestions were true. This is not simply later scholars trying to dismiss the value of the Guide with claims of hearsay.
When one takes a step back for just a moment and tries to look objectively at the Maimonides' intention in writing the Guide for the Perplexed it is pretty clear that we can't simply utilize it as a basis for the types of open inquiries, rationalist thinking, and all the more so the systematic modernization of Judaism we currently see trending today. Let us not forget that the Maimonides himself codified in the Mishneh Torah many laws that are very unpopular and cause many people with more modern orientation to squirm. He certainly never backtracked from any of those positions by writing the Guide for the Perplexed. It would hardly be a strong sign of integrity to then turn around and invoke the Guide for as the source for our modern approach to Torah.