Metaphors involving motion have shaped discussion and understanding of for millennia. Rothfarb (2001, p. 927) points out that ever since ancient times authors have identified motion as a functional aspect of Perhaps the most famous example is the so-called music of the spheres in which Kepler in Harmonices Mundi attempted to connect planetary motion with numerical ratios of musical intervals (Balbi, 2008). St. Augustine in Da Musica defined as scientia bene modulani, which translates as knowledge of correct (MacInnis, 2015), and Rameau's Treatise on Harmony refers to collisions of sounds (Christiansen, 2004). More recently, Shove and Repp (1995) concluded can represent natural forms of motion, Clarke (2001, 2005) concluded the relationship between and motion provides an important part of music's impact and meaning, Eitan and Granot (2006) considered how was associated with bodily movement, and Phillips-Silver (2009) concluded a link between and movement was pervasive in human experience. Consistent with this, Larson (2012) suggested an important metaphor in our conceptualization of is Musical Succession is Physical Motion. Indeed, Larson (2012, p. 50) noted is hard to imagine a term that describes physical motion that has not been, or could not be, applied to music, and he provided many examples of spatial and motion metaphors in (e.g., melodies moving by steps or leaps, melodic contours ascending or descending, presence of passing and leading tones; see also Johnson & Larson, 2003).The purpose here is to review data and theories regarding whether the mental representation of embodies a dynamic of motion. Production of typically requires motion of some sort (e.g., vibration of a string, reed, or drumhead; changing configurations of open [not pressed] and closed [pressed] keys on a musical instrument, etc.), and so in a trivial sense, arises from motion. However, and motion are complex concepts, and not every type of motion is necessarily a potential source of music. Rather than reviewing the relationship between and motion in general, the goal here is simpler: to consider the relationship between and a single consequence of motion, momentum. It is suggested that the mental representation of exhibits momentum-like effects that share many properties with momentum-like effects in other domains of perception, cognition, and behavior. Part 1 explores the notion of musical motion and considers Larson's discussion of musical forces in general and musical inertia in particular. Part 2 reviews information on different (nonmusical) momentum-like effects and considers whether musical inertia is consistent with these effects. Part 3 examines implications and consequences of musical momentum, and considers dynamic representation and functional architecture, an emphasis on extrapolation across time, auditory streaming and perceptual grouping, auditory kappa and tau effects, naive physics of forces, and which aspects of might map on to different components of momentum. Part 4 provides a brief summary and conclusions.Part 1: Music and MotionIt has long been thought that is related to motion (for reviews, see Eitan & Granot, 2006; Phillips-Silver, 2009; Rothfarb, 2001; Shove & Repp, 1995). Motion of a physical object results from physical forces, and the existence of analogous musical forces associated with musical succession in Western tonal was proposed by Larson (2004, 2012; Larson & van Handel, 2005). In Part 1, the idea of musical forces, and the properties of a specific musical force-musical inertia-are considered.Musical Succession and Physical MotionWhat is it that moves in music? Indeed, the idea of musical motion is something of a puzzle, in that unless the source of the (e.g., performer, loudspeaker) is physically moving, the per se does not actually physically move (see Larson, 2012; Zuckerkandl, 1956). …