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Extraterrestrial life - Exoplanets, Habitability, Astrobiology | Britannica
Extraterrestrial life - Exoplanets, Habitability, Astrobiology: For thousands of years humans have wondered whether they were alone in the universe or whether other worlds populated by more or less humanlike creatures might exist. In ancient times and throughout the Middle Ages, the common view was that Earth was the only “world” in the universe. Many mythologies populated the sky with divine beings, certainly a kind of extraterrestrial life. Some philosophers held that life was not unique to Earth. Metrodorus, an Epicurean in the 3rd and 4th centuries bce, argued that Since the Renaissance, fashionable belief has fluctuated. Practically all informed opinion in the late 18th century
