古典來源
拉丁語詞組Deus ex machina（英譯：God from the machine）翻譯自希臘語ἀπό μηχανῆς θεός（apò mēkhanḗs theós），意思是機關跑出的神，中文一般翻譯為舞台機關送神、機械降神、機器神、解圍之神……等。
現代批評
這種手法通常被評論家認為是不高明的說書技巧，因為它破壞了故事的內在邏輯，縱使有時候會為了這個理由而故意採用。繼亞里士多德之後，文藝復興時期評論家將其視為一種迂拙的情節計策，雖然其仍然受用於文藝復興時期的劇作家；莎士比亞將此計策用在《皆大歡喜》、《泰爾親王佩力克爾斯》和《冬天的故事》。19世紀末，尼采批評歐里庇得斯透過這種計策將悲劇因素製造成樂觀的類型，並促使他高度懷疑戲劇《blissful delight in life》是“希臘快樂”（Greek cheerfulness）。
尼采認為deus ex machina對蘇格拉底文化恰好對症下藥，重視文化知識過於酒神節的音樂並最終導致死亡的悲劇：
But the new non-Dionysiac spirit is most clearly apparent in the endings of the new dramas. At the end of the old tragedies there was a sense of metaphysical conciliation without which it is impossible to imagine our taking delight in tragedy; perhaps the conciliatory tones from another world echo most purely in Oedipus at Colonus. Now, once tragedy had lost the genius of music, tragedy in the strictest sense was dead: for where was that metaphysical consolation now to be found? Hence an earthly resolution for tragic dissonance was sought; the hero, having been adequately tormented by fate, won his well-earned reward in a stately marriage and tokens of divine honour. The hero had become a gladiator, granted freedom once he had been satisfactorily flayed and scarred. Metaphysical consolation had been ousted by the deus ex machina.
尼采認為，deus ex machina製造出虛假的慰藉感覺，這是不應該尋求的現象，這種情節計策的詆毀普遍出現在評論意見中。一些20世紀的修正主義者的評論，建議deus ex machina不能在簡化的用語中被查看，並主張此種計策是凡人“刺探”與神的關係。拉什瑞姆（Rush Rehm）特別引用希臘悲劇的例子，其中deus ex machina提供複雜化角色的生活和態度，當面臨神的同時為觀眾帶來戲劇的尾聲。
