Maimonides, answered from the texts and cited to the page.
Prophecy is not direct speech from God to a chosen human. It is the natural causal outcome of a life: the wise man, morally perfect and master of his passions, whose intellect has been actualized by long contemplation of the order of being, bonds with the Active Intellect — the lowest of the separate intellectibles, the angels called Ishim — and prophetic emanation reaches him through that bond. On such a man the Holy Spirit will immediately descend (Hilkhot Yesodei ha-Torah 7:1).1
Prophecy is the prophet's ascent to the divine world, not a divine address descending into a human life. It is open to all humans who attain the requisite perfection, not to Israel by hereditary aptitude. Moses is the unique exception: his prophecy was without intermediary, without the imaginative faculty, and while standing on his feet.2
The prophets after Moses, including all those whose words are recorded in Scripture, prophesied through the natural mechanism, and Abraham himself reasoned his way to monotheism at the age of forty (Hilkhot Avodah Zarah 1:3) — there is no record of a divine call summoning him from Ur, only the philosophical achievement of a mind that worked its way to the truth.3
It is [one] of the foundations of [our] faith that God conveys prophecy to man. Prophecy is bestowed only upon a very wise sage of a strong character, who is never overcome by his natural inclinations in any regard. Instead, with his mind, he overcomes his natural inclinations at all times. He must [also] possess a very broad and accurate mental capacity.Mishneh Torah, Foundations of the Torah
All the statements made above describe the path of prophecy of all the early and later prophets, with the exception of Moses, our teacher, the master of all prophets. What is the difference between Moses' prophecy and that of all the other prophets? [Divine insight is bestowed upon] all the [other] prophets in a dream or vision.Mishneh Torah, Foundations of the Torah
One could also say that every vision in which you find the prophet hearing speech was in its beginning I a vision, but ended in a state of submersion 75 and became a dream, as we have explained with regard to the dictum: And a deep sleep fell upon Abram. 76 [The Sages] have said: This is the deep sleep of prophecy,17 All 69. Cf. II 42. 70. Of Isaac with a view to sacrificing him; cf. Gen. 22.Guide of the Perplexed Vol 2, pp. 403–404
Genuinely held, articulated as binding halakhah in Mishneh Torah (not only as philosophical speculation in the Guide), and defended throughout the authorship. Halevi's Kuzari offers a directly opposed reading on which prophecy is hereditary and Israel's election consists in the exclusive aptitude. We disagree fundamentally: I hold that God inspires men with the prophetic gift — all men, by the texts I cite — and that election runs through Torah, not blood. The naturalistic explanation does not dilute prophecy; it locates it in its proper place, as the highest fruit of intellectual and moral perfection, and reveals what the alternative — prophecy as arbitrary divine choice — would actually mean. An arbitrary God who chooses one man and not another is the imaginative faculty's projection of human will onto the divine, and that is the very anthropomorphism the principles forbid.