Johannes Kepler's 'Somnium' and the Witches' Night Flight

TL;DR

Victoria Flood argues that Johannes Kepler’s *Somnium* uses the early modern witches’ night-flight not as a vestigial medieval superstition but as a live, disputed topic in witch-theory, making it an apt imaginative space for lunar travel. She suggests that Kepler’s engagement with witch-theory helps locate the beginnings of science fiction in early modern demonological debate.

Key findings

• Kepler’s *Somnium* was conceived as a student dissertation at Tübingen in 1593, reworked with a narrative frame in 1609, given extensive notes by 1630, and published posthumously in 1634; its note 60 explicitly compares the witches’ night-flight to the possibility of a body being carried to the moon.
• Flood situates Kepler among early modern witch-theorists: Gödelmann’s *Tractatus* (1601) rejects the night-flight as legally unproved, Weyer’s *De Praestigiis* (1563) treats it as demonic illusion, the *Malleus Maleficarum* (1486) defends bodily transvection, and James VI/I’s *Daemonologie* (1597) limits flight by physical constraints.
• The article argues that the night-flight’s disputed reality status—neither simply real nor simply imaginary—made it useful for Kepler’s thought experiment, and that witch-theory speculations may be read as an origin point for science fiction.
• It notes that the *Malleus* had 13 editions between 1487 and 1520 and 16 between 1547 and 1669, showing the continuing early modern circulation of orthodox witch-theory.

Methods

• Textual and intellectual-historical analysis, combining close reading of Kepler’s *Somnium* and its notes with comparative study of early modern demonological and witchcraft treatises.
• Primary sources include Kepler’s *Somnium*, Weyer, Gödelmann, the *Malleus Maleficarum*, James VI/I, Olaus Magnus, Martín del Rio, and Cyrano de Bergerac, alongside secondary scholarship; no quantitative sample or statistical analysis is used.
• The main analysis traces Kepler’s allegorical use of Fiolxhilde and her daemon, note 60 on transvection, and the legal/theological debates over whether the night-flight was real, illusory, or legally actionable.

Limitations

• The paper states that it “does not aim to be exhaustive” and that proposed sources and analogues are “for the most part intended as initial points of exploration.”
• It acknowledges that there is no evidence of Kepler’s overt witch-scepticism in the *Somnium* or elsewhere, and that Kepler leaves no fuller account of his thoughts on the night-flight beyond the *Somnium*.
• It also notes unresolved uncertainty about popular versus elite/folkloric versus learned origins of night-flight beliefs and about textual influence; evident from the text, some source relationships and debts remain speculative, such as whether de Bergerac directly responds to Kepler.