Ron,
To be honest I found the following concerning Rambams position concerning Astrology... You are correct that he doesnt agree with Chazal about it...
This does discuss the idea which I brought out concerning the fact that Jews are above Mazel..
http://www.cckollel.org/html/Parasha/bereishis/Lechlicha-2002.htmHalacha Encounters
Astrology in Halacha
Rabbi Ari Friedman
Throughout Shas and the Medrashim, Chazal often attribute both world events and people’s destinies to Mazal. Mazal is defined as the power given by Hashem to the celestial bodies to influence His world. In spite of this, the Gemara states clearly that from the Pasuk “Tamim Tihiyeh im Hashem Elokecha, And you shall be pure before Hashem your G-d” we are prohibited to consult with stargazers (Devarim, 18, 13; Psachim 113b). The Shulchan Aruch also mentions this prohibition (Y.D. 179-1). Let us explore this topic and attempt to clarify its Halachic ramifications.
To begin, the Rambam (A.Z. 11, 8-9) writes that to calculate times of good or bad luck, or to take action based on astrology is an issur lo sa’aseh (negative commandment) grouped with other prohibitions of witchcraft and sorcery. Even consulting with astrologers without taking any action upon their conclusions is prohibited, for it is dealing with falsehood. The Rambam goes on to explain his opinion that all such practices are utter foolishness. This stance of the Rambam is expressed throughout his many writings. He always claims that astrology, sorcery and the like are baseless practices and those who claim to predict the future based on stars are either fools or fooling others.
Many Rishonim, namely the Ramban (Teshuvos Hameyuchasos #283) strongly disagree with the Rambam, citing numerous ma’amarei Chazal (statements of our Sages found in the Talmud) validating astrology. They maintain that although the Torah prohibits such practices, there is nevertheless real wisdom to be found in astrology.
Now that we have presented this view, let us continue and understand a Midrash quoted by Rashi in this week’s Parasha (15,5 Shabbos 156B). Avraham says to Hashem, “I have looked into my astrology and I am unfit to bear a child.” Hashem replies to this observation, “ Leave your astrology, Ein Mazal L’Yisrael (There is no such concept as “Mazal” when it somes to the Jewish People).” Hashem continues, “On what basis do you determine this? Is it because Tzedek (Jupiter) is in the west- (the cold region signifying the inability to bear children)? I will move it to the east.” The Gemora continues to relate other instances where astrologers predicted misfortunes which were avoided through the z’chus (merit) of tefillah or tzedaka. The Rishonim explain that all agree that the constellations influence events in this world. “Ein Mazal L’Yisrael” means that B’nai Yisrael have the ability to override their supposed fate through Torah and Mitzvos. Only those who are not close to Hashem are thrust under the “rule” of the constellations, but as members of Klal Yisrael, we may rise above any intermediary (Nimukei Yosef Sanhedrin 16B, Ran,Tosfos in Shabbos see also Sifsei Chaim on Mazalos)
It is for this reason that the Torah tells us “Tamim Tihyeh.” Do not look into astrology - you are above it. However, the Ramban adds, although the Torah prohibits us to approach astrologers and inquire regarding our Mazal, if they happen to inform us and warn us to be aware of a certain bad Mazal, we must heed their warning and not rely on a miracle. Only someone of Avraham Avinu’s caliber is expected to totally ignore Mazal.
What remains for us to clarify is that the Gemora itself discusses various Mazalos and their effect on people. For example, the Gemora states that somone born under the Mazal Tzedek (Saturn) will be charitable. And someone born under Ma’adim (Mars) will be a spiller of blood. How could Chazal involve themselves in a practice which is seemingly assur? The explanation seems to be that the Torah prohibition is to predict with accuracy future events. The future is controlled ultimately by Hashem and we need not delve into astrology. What Chazal are telling us when discussing Mazalos is that people under the influence of a certain Mazal may have a tendency and predisposition towards a particular trait. This knowledge may be used to direct a person in building and developing his character. Other statements made by Chazal regarding Mazalos should be understood in this vein as well.
As for the Halacha in our times, those posing as astrologers may be assur to consult with for either of two possibilities.
1- They are genuine astrologers (highly doubtful) and thereby assur because of “Tamim Tihiyeh”.
2- They are phonies and are assur under the law of “Lo Senachashu” (see Ramban and Tamim Tihieh p. 26-34).
However, the study of Chachmas Hamazalos in the nature of Chazal as mentioned above is permitted. As for the horoscopes featured in various publications, they should be treated with the same seriousness as the rest of the material contained within those pages.