Does life exist on other planets? What is the Torah’s perspective?
The approach of the scientists: So, as you may know, there is no answer for this question. Scientists and astronomers have no definitive proof of either the negation of the existence of extraterrestrial beings, otherwise known as aliens, nor do they have any proof to show that they exist, as we have yet to formally discover any existence in any other planet that we have visited or taken pictures of. Thus, the fact that we find scientists and astronomers who strongly believe one of these two approaches, with some vehemently defending their belief that there may be thousands of other civilizations on other planets throughout the universe and its galaxies, and others saying that the conditions found on planet Earth are so unique that life cannot exist in any other area, practically neither of them actually know for a fact which of the two approaches is correct, and chances are that we will never find out, and perhaps are not meant to find out. All of the different testimonies and sightings of aliens and UFOs that have been collected, do not reach the bar of evidence to be able to conclude that in truth aliens do exist. In addition, in Jewish literature the existence of demons and other subhuman creatures are mentioned, and it is hence totally possible that even if we were to accept the testimonies as true, perhaps it is these demons that they have been seeing, and not aliens from other planets.
The approach of the Torah-Scripture: Scripture, which serves as the source of the description of creation, does not mention explicitly the existence of extraterrestrial beings. Some deduce from the fact that Scripture states that God created man and all living creatures on earth, that it comes to negate the creation of living creatures on any other planet.
The approach of the Talmud and its Mefarshim: One source that seems to point to the existence of creations on other planets is the Talmud in Tractate Moed Katan 16a on the verse in Shoftim 5:23 “Cursed be Meiroz, says [Barak] the messenger of G-d, may its inhabitants be cursed, as they did not come to assist in the battle of Hashem.” This verse speaks of a curse that Barak placed against the people of Meiroz for not having come to assist them in battle against Sisera. The above Talmudic source speaks of the identity of Meiroz, in its search for sources dealing with excommunication for one who does not appear to court. In its first interpretation it says that Meiroz is the name of some great general who was placed in excommunication for not coming to assist them in the battle. In a second interpretation, the Talmud states that Meiroz is the name of a star or planet, as the verse states that from heaven the stars fought against Sisera, and seemingly the above star called Meiroz did not show up to the battle. Now, the question is raised as to what is the meaning that the star did not come to help in the battle and the fact that it, and its inhabitants, were cursed. One simple interpretation is that it is in reference to the constellations which have an effect on people below and on the outcome of a battle, and this star did not help influence the Jewish people to win the battle and was thereby cursed. Rashi on the Talmud gives a bit of a deeper explanation saying that this star was in fact the constellation of Sisera and he did not come to assist in the battle against him and was thereby cursed. According to this interpretation, some Mefarshim explain that the concept of inhabitants of Meiroz, which is later mentioned in that verse, can be interpreted to refer to the surrounding stars that orbit around the star called Meiroz, and that likewise did not help assist the Jewish people in the battle against Sisera and therefore were included in the curse. However, other Mefarshim claim that according to the second interpretation of the Talmud, the concept of inhabitants should be taken in the literal sense, and that it refers to physical inhabitants which live on the star of Meiroz, and that they too have been cursed. In other words, according to this approach, the Talmud is explicitly saying that there exist physical aliens on other planets. Indeed, the Lubavitcher Rebbe embraced this approach as a valid source in Torah for the existence of aliens, and concluded based on it that aliens do exist, as will be explained below.
The approach of the Jewish philosophers: The main Jewish work of science and philosophy which discusses the existence of aliens is the Sefer Habris of Rabbi Pinchas Horowitz. He writes there as follows [free translation]: “There are many great Gentile philosophers who believe that the stars are physical worlds which contain people and animals and plant life just like this world…. They say that ….it is preposterous to suggest that God created civilization only in our world and that the rest of the universe has no purpose. This is similar to having acres upon acres of farmland with only a tiny sliver of land being used to actually grow anything…. So, let me now comment on this, without doubt God did not create the rest of the universe for no purpose and certainly they contain creations which are there to somehow benefit mankind…. A good proof for this position is from the Talmudic statement discussing the verse in which Barak curses Meiroz [as explained above in length in the approach of the Talmud]…. I am sure that all of these worlds are not similar to each other and each one has a specific form of nature as well as a specific form of creations. It is not possible to say that these creatures on these other planets are made up of the four elements like our world, as if so then it would not be possible for them to survive the heat or cold… Rather they must have been created from different and more sublime elements than us, and are considered higher creations than those on earth. A simple observation of this concept can be seen from sea creatures which are made of completely different element and nature than creatures of the land. Nonetheless, it is certain that human beings such as us do not exist on these planets or stars even though it is possible that intelligent beings do exist, as it is not possible for them to have freedom of choice and therefore likewise the concept of the Jewish religion and Torah and Mitzvos can only exist in our world.” I am not aware of any discussion on the question of whether extraterrestrial beings exist on other planets amongst the works of the earlier Jewish philosophers.
The approach of the Zohar and Kaballah: Another area commonly pointed to as a source in Torah which speaks of extraterrestrial beings is the Zohar which speaks of the existence of seven lands which contain seven names with inhabitants that are different than the human race or any living creature that we know of on earth. However, in truth this Zoharic statement speaks nothing of creations that live in other planets as it is referring to our own planet Earth and that earth contains seven levels within it, ours being the most exterior level which rests on the surface, with there being six other levels under it with some containing civilizations and creations just like us. The source states that each one of these lands that are inside the earth contain their own atmosphere. While this is certainly a fascinating topic to ponder as to whether there are creations and other human like figures living right under us in planet Earth, it makes no mention of the existence of extraterrestrial beings on other planets. Indeed, the famous Kabbalist Rabbi Mordechai Sharabi is quoted to say that based on the teachings of the Arizal, creations do not exist in any planet other than planet Earth.
The approach of the Lubavitcher Rebbe: The Lubavitcher Rebbe in a talk in 1969 addressed the question of whether the existence of extraterrestrial beings is possible according to Torah. In his conclusion, he states that not only is it a possibility according to Torah, but that in truth so is proven from the above Talmudic statement that inhabitants exist not only on planet Earth but also on additional planets. Interestingly, however, he writes that the human race on planet Earth must be the most intelligent of all creations and that they are smarter and more intelligent than any creations that are found in additional planets. The following is his full statement [free translation]: “Regarding the question that has been raised lately if there are creations and living creatures etc. on the moon, in truth it is seemingly superfluous to even have such a discussion being that it’s answer is irrelevant to the fulfillment of Torah and Mitzvos. However since we are lately very enthusiastic about Mivtza Tefillin, and it’s possible that if a person knows the answer to this question then another Jew will agree to put on Tefillin, or keep Shabbos or kosher and the like, therefore when I was asked this question by an individual I answered him that the answer to this is found in the Talmud.” The Rebbe then went on to explain the above proof from the Talmud, as brought above and concluded, “according to the second interpretation in the Talmud that it is a star, one must conclude that the inhabitants discussed in the verse refer to inhabitants that live on this star. And from this it is proven that there are inhabitants not just on planet Earth but also in additional planets. Nevertheless, the people found on planet Earth are of greater stature than the creatures found on other planets, as it is for this reason that the Torah was given specifically on planet Earth” This approach of the Lubavitcher Rebbe said in a public talk, was testified by Dr. Velvl Greene to be not just the expression of an opinion but the opening of a search mission for extraterrestrial life. Dr. Velvl Greene [who worked as a scientist for NASA in the Planetary Quarantine Division, which was then charged with trying to find life on Mars] had various audiences with the Rebbe on this subject of extraterrestrial life existing on other planets and from those meetings the following was allocated.
- The Rebbe showed great interest in his work and encouraged Dr. Green to actively search for life on Mars and if he could not find it on Mars and he should look for it on another planet. He also requested from him, and eventually pressured him, to supply unclassified material from his research.
- The Rebbe stated to him that saying that creatures do not exist on other planets could be viewed as limiting God’s ability of creation, as in truth God is infinite and is capable of all.
The final word: While the subject of extraterrestrial beings is one that continues to consume the minds of many people, scientists, astronomers, book writers, movie directors, and simple people stricken with curiosity of the unknown, it is not a subject that a Jew needs to, nor should, spend time on, and other than knowing that their existence is possible even according to Torah, his main occupation should be in studying the wisdom of the Torah and not pondering matters beyond his reach. Not all secrets of creation does God want a person to try to crack, however certainly he wants us to study his Torah and abide by his teachings and spend our time involved in doing so.
The existence of extraterrestrial beings is not negated by Torah, and on the contrary, there are Torah sources which can be interpreted to point towards their existence, and so was the belief of the Lubavitcher Rebbe that they indeed can exist. Whatever the case, other than scientists assigned to this field, one should not spend too much of his time researching this subject in expense of his Torah learning.
 See Sefer Hamahapach [Zamir Kohen] pp. 56-60
 An astronomer named Dr. Frank Drake in the 1960s publicized his opinion that in his estimate there are about 10,000 other civilizations on planets in our galaxy alone. The scientist Dr. Carl Sagan agreed with this approach and stated that there even more civilizations than what Dr. Drake believed. [Hamahapach ibid] See Sefer Habris 1 Mamar Gimel Chapter 2 that there are many great Gentile philosophers who believe that all the stars are physical worlds which contain people and animals and plant life just like this world, while some believe that only those stars which don’t shine are like our world. They say that if our small planet is inhabited then certainly the larger planets are inhabited, and that it is preposterous to suggest that God created civilization only in our world and that the rest of the universe will have no purpose. This is similar to having acres upon acres of farmland with only a tiny sliver of 1 x 1′ being used to actually grow anything. [Hamahapach ibid]
 Many scientists today are taking to the belief that we are alone in the universe due to the unique living conditions that need to take place for there to be left on another planet. So concludes the astronomer Dr. Donald Bromley and Dr. Peter Word from the University of Washington in their book that they co-authored the “Rare Earth”
 See Hamahapach ibid
 See Chagiga 16a; Zohar Vayikra p. 276; Avos Derebbe Nasan
 Hamahapach ibid that so stated many Gedolei Yisrael in 1969 when question about there being civilization on the move
 “With 400 Shofros Balak excommunicated Maruz. Some say this is a great person. Others say that it is a star.”; See also Shavuos 36a
 Rashi 5:23
 Rabbeinu Yechiel Miparish on Moed Katan ibid; Rabbeinu Chananel ibid, mentioned [and negated] in Sicha of Rebbe brought below
 Sefer Habris of Rabbi Pinchas Horowitz Mamar Gimel “According to the opinion that it is a star, since it says in its inhabitants will be cursed, we must conclude that it has inhabitants and that the curses befalling both the star and all its inhabitants were not coming to help God.”
 This does not necessarily contradict Rashi and is simply coming to say that once this star which was the constellation of Sisera was cursed its inhabitants were likewise cursed with it.
 Sefer Habris 1 Mamar Gimel Chapter 2-4; To note that the Rebbe Rayatz discouraged the study of books such as these if it will come in expense of studying the classical Jewish works necessary for every Jew to know, such as the Mishneh, and Talmud, and Tanach, etc. [See Igros Kodesh Rayatz 6:113]
 Some have, in my opinion, erroneously credited Rav Chisdaiy Karshekash [a major Jewish philosopher from Spain in the 14th century] with having discussed this question. In truth, when studying his work “Or Hashem” one finds no such reference to such a question, and in the quoted source of Mamar 4 Derush 3 he simply speaks in regards to whether the celestial beings are alive and speak, which is a matter of open discussion which contain ample arguments for each side. Meaning are the sun and moon and stars alive and do they speak and praise God. However, no mention is made of the existence of creatures on the celestial beings, and hence what he discusses is not relevant to our question. However, in the Sefer Habris of Rabbi Pinchas Horowitz he seems to credit the Sefer Haikkarim, by Rav Yosef Albo, with discussing this topic and negating, and I have yet to find the source inside.
 Zohar Bereishis p. 39-41 and Vayikra p. 10; Meiam Loez Bereishis on Chapter 1:9
 Sefer Tzeva Hashmayim 1:250, written by the astronomer Dr. Vidal; Hamahapach ibid
 Sichas Parshas Devarim Shabbos Chazon 4th Menachem Av 1969, printed in Toras Menachem Vol. 57 pp. 172-174; This talk took place shortly after the moon landing which occurred on 20 July 1969
 Thus, the Rebbe negates the possible understanding of the position of the Sefer Habris that the extraterrestrial beings are more intelligent than the human race and simply don’t have freedom of choice, and says that man is the most intelligent of all creations. To note, that the famous sci-fi writer and author Isaac Asimov was forced to avoid writing on aliens in his literature being that he depicted them as being more intelligent than the human race and is editor-in-chief refused to allow even sci-fi stories to depict humans as being of lower intelligence than aliens.
 See the Sicha of Rebbe ibid where he initially negates entertaining the question of extraterrestrial life being that it has no ramification for a Jews service of God. See also Rambam Pirush Hamishnayos Chagiga chapter 2 they do should not be involved in pondering about what exists under the earth on top of the earth as this is not a job or function and God is not desire him to research but rather to simply learn his Torah; See also Rambam Hilchos Yesodei Hatorah end of chapter 4; Meiam Loez beginning of Bereishis
 As for the claim that researching the subject brings one to fear of heaven and discovery of God’s greatness, while certainly studying the nature of creations and how it expresses the greatness of God is a mitzvah and obligation, this too needs to have limitations, as Maimonides writes after authoring the first chapters of his magnum opus Mishneh Torah, that even Maaseh Bereishis is not meant for one to stroll in but simply to learn the basics that we already know and excite our minds to God’s greatness through them. [See Rambam Hilchos Yesodei Hatorah end of chapter 4]