Q. What is Horav Miller's opinion in regards to intelligent life in other planets? Does the Torah accept it as a possibility?
A. Rabbi Aryeh Kaplan Zt"l (The A.K. Reader) mentions that one of the first to discuss the question of extraterrestrial life in general was Rabbi Chasdai Crescas (Or Hashem 4:2). After a lengthy discussion, he comes to the conclusion that there is nothing in Jewish theology to preclude the existence of life on other worlds. As possible evidence for extraterrestrial life, he quotes the Talmudic teaching (Avoda Zara 3b) that "God flies through 18,000 worlds." Since they require His providence, we may assume that they are inhabited.
The exact opposite opinion is that of Rabbi Yosef Albo, author of the "Ikkarim." He states that since the universe was created for the sake of man, no other creature can exist possessing free will. Since any extraterrestrial life would neither have free will nor be able to serve a creature having free will (as terrestrial animals and plants serve a terrestrial man), they would have no reason for existing and therefore be totally superfluous. One could bring some support to the second opinion from the Talmudic teaching that every land where it was not decreed for man to live was never subsequently inhabited. However, here again, it is not absolute proof, since this may only refer to our planet.
Between these two extremes, we find the opinion of the Sefer Habris who states that extraterrestrial life does exist, but that it does not possess free will. The latter is the exclusive possession of man, for whom the universe was created. The 18,000 worlds mentioned earlier, in his opinion, are inhabited physical worlds. The proof that he brings for his thesis is most ingenious. In the song of Deborah, we find the verse, "Cursed is Meroz... cursed are its inhabitants" (Judges 5:23). In the Talmud, we find the opinion that Meroz is the name of a star. According to this opinion, the fact that Scripture states, "Cursed is Meroz... cursed are its inhabitants" is clear proof from the words of our Sages for extraterrestrial life. (Excerpts quoted by Torah org.)
Rabbi Menachem M. Schneerson Zt"l, the Lubavitcher Rebbe mentioned "One who declares that there is no life besides on earth is limiting the Creator's abilities." (Sichas Hashavua Shoftim 5749)
Horav Shlomo Miller's Shlit"a opinion is that although many contemporary scientists believe that it is only a matter of time until extraterrestrial life is discovered, that is not the Torah view. There is indeed an extreme large number of stars in the universe (10 x 18 power according to Rabbi Kaplan understanding of Talmudic and Midrashic sources, contemporary estimates from astronomers vary between 10 x 21 to 10 x 24 approximately,) however, any likelihood for the development of intelligent life on the planets they may contain would reasonably be similar to the chances of that happening on planet Earth. That probability is mathematically non-existent for believers in the truth of the Torah. It would require the will of Hashem to create such life. From what we understand from our Torah, no clear indication or need for their existence is mentioned.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit"a.
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