人有三气。卫气出于上焦（据《素问》注），荣气出于中焦，二者皆气也；二气合行于心
肺之间，则积而为宗气，本无形质，必有所附丽以行。故荣行脉中，附丽于血；卫行脉外，
附丽
于津。惟血随荣气而行，故荣气伤则血瘀；津随卫气而行，故卫气衰则津停。治血以运化荣
气为主；治津以温通卫气为主。知乎此，而荣血、卫气之说可以息矣。且也，血所以濡脉，
津所以濡筋。（伤寒汗后，四肢拘急，此津不濡筋之故），而荣之行，自手太阴始，故《灵》
经脉篇序十二经以手太阴为端；卫之行，自足太阳始，故《灵》经筋篇序十二经以足太阳为
端
。知乎此，而心荣、肺卫之说可以息矣。（卫出上焦，据王《素问》注。今《灵枢》“上”
作“下”，误。）
病之得于岁气者，一自正气来，一自时气来。正气为病，以伤寒、伤暑为最着；时气为
病，
以冬温、寒疫为最着∶皆以其极偏也。正气，太一方之王气，本不病患，而人自触之，谓之
以人干天；时气，对冲方之戾气，本能病患，而人适中之，谓之以天令人。以人干天，则触
之者病，而不触者无与焉；以天令人，则中之者固病，而不中者即染之。人气处于独，天气
统于同，所以正气病无易，时气病有易也。正气虽过中而非厉，时气即稍弱而已毒。所以正
气病，纵如伤寒、伤暑之重而不易；时气病，纵非冬温、寒疫之重而亦易也。今伤风咳嗽有
相易者，以此咳嗽亦自时气来。
There are three Qi in the human body. Wei Qi (Defensive Qi) originates from the Upper Jiao (Upper Burner, according to the commentary on *Suwen*), and Ying Qi (Nutritive Qi) originates from the Middle Jiao (Middle Burner); both are forms of Qi. When these two Qi circulate together between the Heart and Lungs, they accumulate to form Zong Qi (Gathering Qi). Zong Qi has no inherent form or substance and must adhere to something to move. Therefore, Ying Qi moves within the vessels, adhering to Blood; Wei Qi moves outside the vessels, adhering to Jin Ye (Body Fluids). Since Blood moves with Ying Qi, injury to Ying Qi leads to Blood stasis; since Jin Ye moves with Wei Qi, decline in Wei Qi leads to stagnation of Jin Ye. Treatment for blood disorders focuses primarily on promoting the circulation of Ying Qi; treatment for fluid disorders focuses primarily on warming and unblocking Wei Qi. Understanding this renders the debates over Ying-Blood and Wei-Qi distinctions obsolete. Furthermore, Blood moistens the vessels, and Jin Ye moistens the sinews. (After sweating due to Cold Damage, spasticity and urgency in the four limbs occur because Jin Ye fails to moisten the sinews.) The movement of Ying Qi begins with the Hand-Taiyin Lung Meridian; thus, the *Lingshu* chapter "Meridians" lists the Twelve Meridians starting with the Hand-Taiyin. The movement of Wei Qi begins with the Foot-Taiyang Bladder Meridian; thus, the *Lingshu* chapter "Sinews" lists the Twelve Meridians starting with the Foot-Taiyang. Understanding this renders the theories that the Heart governs Ying and the Lungs govern Wei obsolete. (Wei Qi originates from the Upper Jiao, according to Wang Bing's commentary on *Suwen*. In the current text of *Lingshu*, "Upper" is written as "Lower," which is an error.)
Diseases acquired from the Annual Climate (Sui Qi) come from two sources: one from Zheng Qi (Regular/Normal Qi) and one from Shi Qi (Seasonal/Abnormal Qi). Diseases caused by Zheng Qi are most notably Cold Damage (Shanghan) and Summerheat Injury (Shangshu); diseases caused by Shi Qi are most notably Winter-Warmth (Dongwen) and Cold Epidemic (Hanyi): all because their deviations are extreme. Zheng Qi is the Sovereign Qi of the Central Direction; it does not inherently cause disease, but people contract it by offending it, termed "Man offending Heaven." Shi Qi is the malevolent Qi of the opposing direction; it inherently causes disease, and people contract it by being hit by it, termed "Heaven causing Man to suffer illness." When Man offends Heaven, only those who offend it become ill, while those who do not are unaffected; when Heaven causes Man to suffer illness, those hit by it certainly become ill, and even those not directly hit may contract it. Human Qi exists in uniqueness, while Heavenly Qi is unified under common laws; therefore, diseases from Zheng Qi are non-contagious, while diseases from Shi Qi are contagious. Although Zheng Qi can be excessive and fierce, it is not a pestilential pathogen; Shi Qi, even if slightly weaker, already possesses toxicity. Thus, diseases from Zheng Qi, however severe like Cold Damage or Summerheat Injury, remain non-contagious; diseases from Shi Qi, however mild compared to Winter-Warmth or Cold Epidemic, remain contagious. Currently, wind-cold coughs show contagion because such coughs also originate from Shi Qi.