In two-part voice-leading, there are four types of motion: parallel, similar, oblique, and contrary. Alternatively, voices may not move at all and remain stationary. ## Parallel Motion Parallel motion between two voices occurs when both voices move in the same direction by the same melodic interval. Only the generic size of the melodic interval matters, not the specific quality. In **Example 1** below, both voices move upward by seconds. The upper voice moves by minor second from B to C while the lower voice moves by major second from G to A. Because parallel motion preserves the generic size of the starting and ending harmonic intervals, we would say of **Example 1** that the voices are “moving in parallel thirds.” **Example 1.** Parallel motion. ![[types of motion example 1.png]] ![[types of motion example 1.mp3]] ## Similar Motion Similar motion between two voices occurs when both voices move in the same direction but by different melodic intervals. In **Example 2** below, both voices move upward but the upper voice moves by major second from A to B while the lower voice moves by perfect fifth from C to G, resulting in harmonic intervals of a sixth and a third. **Example 2.** Similar motion. ![[types of motion example 2.png]] ![[types of motion example 2.mp3]] ## Oblique Motion Oblique motion between two voices occurs when one voice remains stationary while the other voice moves. In **Example 3** below, the upper voice remains stationary (repeating the same pitch) while the lower voice moves downward from F to D, resulting in harmonic intervals of a third and a fifth. **Example 3.** Oblique motion. ![[types of motion example 3.png]] ![[types of motion example 3.mp3]] ## Contrary Motion Contrary motion between two voices occurs when one voice moves upward while the other voice moves downward. In **Example 4** below, the upper voice moves downward from C to B while the lower voice moves upward from E to G, resulting in a sixth and a third. **Example 4.** Contrary motion. ![[types of motion example 4.png]] ![[types of motion example 4.mp3]] ## Stationary Voices When both voices repeat their previous notes, no motion has occurred, and the voices are said to be **stationary**. In **Example 5** below, the upper voice repeats C while the lower voice repeats F, preserving the perfect fifth between both voices. It should be noted that the voices do not move in [[Parallel Fifths]] since no motion has occurred. Rather, we call this an instance of [[Stationary Fifths]], which are permitted in four-part voice-leading, but not in [[Species Counterpoint]]. **Example 5.** Stationary voices. ![[types of motion example 5.png]] ![[types of motion example 5.mp3]]