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The Chi (Slow) pulse belongs to Yin. It beats three times per *xi* (one respiratory cycle), which is less than the Chi (Sluggish) pulse and does not reach four beats. If it beats twice per *xi*, it is a Sun (Damage) pulse; if once per *xi*, the Yuan Qi (Primal Qi) is exhausted, and the disease is incurable. If it beats only once every two *xi*, the Zhen Jing (True Essence) has been depleted, and there is no Zheng Qi (Upright Qi) in the pulse. Even if a Floating-Large, Deficient-Scattered, Kou (Hollow)-Ge (Leather), Floating-Small, Ru (Soggy)-Wei (Minute), or Sinking-Small, Fine-Weak pulse appears, it is merely the remaining flame of an extinguishing lamp. A Slow pulse that is also Floating-Large may indicate a Xu (Deficient)-San (Scattered) pulse or a Kou-Ge pulse. A Slow pulse that is Floating-Small is either a Ru or Wei pulse. A Slow pulse that is Sinking-Small is either a Xi (Fine) or Ruo (Weak) pulse. A Slow pulse that is Fine indicates insufficient force for smooth flow, termed Se (Choppy). In a Choppy pulse, the flow is difficult and choppy, prone to scattering, and may have occasional pauses, but the pause is followed by resumption; this is not a sign of organ failure. The Jie (Knotted) pulse is slow with occasional pauses, where the pause is followed by resumption. This differs from the Choppy pulse, which scatters easily after a single pause. The Dai (Intermittent) pulse is slow with a pause that cannot resume immediately (as stated in the *Mai Jing*: "cannot return on its own," thus moving again later). It resembles the concept of "substitution," having an exit without an entry, and a departure without a return.

The Shu (Rapid) pulse belongs to Yang. It beats six times per *xi*. Seven beats per *xi* is the Ji (Fast) pulse; eight beats is the Ji (Extreme) pulse; nine beats is the Tuo (Loose/Dispersed) pulse. A Rapid pulse that is Floating-Large is called Hong (Surging). A Rapid pulse that is Sinking-Large is Lao (Firm) or Shi (Excess). If the flow is smooth and slippery, it is Hua (Slippery). If it is forceful, it is Jin (Tight). If a Rapid pulse appears at the Cun (Inch) position with intermittent pauses, it is called Cu (Hasty). If a Rapid pulse appears as a Dong (Moving) pulse at the Guan (Bar) or Zhong (Middle) positions, one can palpate a quivering, trembling sensation, resembling a small bean jumping. This describes the morphology of the Rapid pulse and its relationship with other pulses. A normal pulse has four beats per *xi*; even with a deep breath (*tai xi*), it should not exceed five beats. Six beats per *xi* constitutes the Shu (Rapid) pulse, indicating Qi movement that is rapid and exceeds normal limits, hence belonging to Yang. Seven beats per *xi* indicates faster Qi movement, hence called Ji (Fast). Eight beats per *xi* indicates extreme Yang heat. Nine beats per *xi* indicates the dispersion of Yuan Shen (Primal Spirit), similar to the depletion of essence seen in the Slow pulse. A Rapid pulse that is Floating-Large is named Hong (Surging); a Rapid pulse that is Sinking-Large is either Lao (Firm) or Shi (Excess); a Rapid pulse with smooth flow is named Hua (Slippery); a Rapid pulse that is forceful is named Jin (Tight) (as stated in the *Mai Jing*: like a turning rope, like cutting a cord, bouncing as if rapid). If a Rapid pulse occasionally presents a pause, it is called Cu (Hasty) because the rapid flow occasionally fails to continue consecutively (Zhang Zhongjing stated: Excess Yang leads to a Hasty pulse, so it is seen at the Cun position). If a Rapid pulse appears at the Guan position, it is called a Dong (Moving) pulse. The Guan position is where Yin and Yang intersect; when Yin and Yang are disharmonious and antagonize each other, they cause quivering tremors. However, lacking head and tail above and below, confined to the Guan section, only a round, solid small bean can adequately describe its appearance.