外感邪未入里，则知味而食如常，入里则不思食矣。喜冷者，内热也。喜热者，
里寒也。得食稍安者，虚也。得食更甚者。实也。（虚人过食亦不安。）病由饮食而致者，
须问所伤何物。热者必渴，喜冷冻饮料，饮必多。若喜热饮，或冷冻饮料而不多，乃虚热，
非实热也。（火虚者，必不能饮冷。水虚者，虽火燥津干，然少得清润即止，以本虚，不能胜
水之冷气，故不能多饮也。）
大小便不禁，为肾败。（肾开窍于二阴，肾败则失其闭脏之职。）小便清白而长者，必非热
证。（亦有火在上焦者，导之使下则反黄矣。）黄赤而短者，热也。然劳倦生火，或思虑动火，或
泻利忘阴，或阴虚内热等证，小便多黄，虽亦为热，然是虚热，非实热也。津液由
于气化，气病则小便不利。气上脱者，必无小便。气闭者，亦无小便。小腹硬痛，
小便不利，为溺涩。利而大便黑，为蓄血。泻而腹满者，死。大便闭结，腹坚满，
痛不可按者，热结也。大便泻利为寒，然亦有热者，经所谓暴注属热也。（火性急速，
不及传化即出也。其势急迫，辟辟有声，如蟹沫然。若热随泻去，痛随利减，可不治。）又有
纯泻清水者，谓
之热结旁流。（内有燥矢。结成弹丸，挡住糟粕，止于其旁漏下清水也，必极臭。）皆热证也。
又大便鸭
溏者，为寒。色如霉酱，粘腻（不见糟粕颗粒也，为热所烁化之故。）极臭者，又为热。
外感邪气尚未入里时，患者味觉正常，进食如常；若邪气入里，则会出现食欲不振的情况。喜欢冷饮的，是体内有热。喜欢热饮的，是里有寒。进食后症状稍缓解的，属于虚证。进食后症状加重的，属于实证。（体质虚弱的人如果吃得过多，也会感到不适。）疾病由饮食不当引起的，必须询问损伤了何种食物。有热的必然口渴，喜欢喝冷冻饮料，且饮用量大。如果喜欢热饮，或者虽然喜欢冷冻饮料但饮用量不多，这是虚热，不是实热。（阳气虚弱的人，一定不能喝冷饮。阴液虚弱的人，虽然因火燥导致津液干枯，但只要少量摄入清润之物即可停止饮水，因为本质是虚，不能承受水的冷气，所以不能多喝。）
大小便失禁，是肾气败绝的表现。（肾开窍于前后二阴，肾气败绝则失去其固摄脏腑的功能。）小便颜色清白且量长的，一定不是热证。（也有上焦有火的情况，通过引导使火下行后，小便反而会变黄。）小便黄赤且短少的，是热证。然而，劳累过度产生内火，或思虑过度扰动心火，或因腹泻痢疾耗伤阴液，或阴虚内热等证候，小便多呈黄色，虽然也是热，但是虚热，不是实热。津液的生成与排泄依赖于气化功能，气机病变则小便不利。气机上脱的，一定没有小便。气机闭塞的，也没有小便。小腹硬痛，小便不通畅，称为溺涩（排尿困难）。排便通畅但大便黑色，是蓄血证。腹泻且腹部胀满的，预后不良（死证）。大便干结闭阻，腹部坚硬胀满，疼痛剧烈不可按压的，是热结证。大便泄泻通常属寒，但也有属热的情况，正如经典所说“暴注下迫属于热”。（火热之性急速，食物来不及消化传导就排出了。其势急迫，肠鸣音明显，像螃蟹吐沫一样。如果热随泻出，痛随利减，可以不治自愈。）又有纯粹泻出清水的，称之为热结旁流。（肠道内有燥屎结成弹丸状，阻挡住糟粕，只有旁边的清水漏下来，气味极臭。）这些都属于热证。另外，大便像鸭粪一样稀溏的，属于寒证。颜色像霉酱一样，粘腻（看不见糟粕颗粒，是因为被热邪煎熬消化的缘故），气味极臭的，又属于热证。
When external pathogenic factors have not yet entered the interior, taste remains normal and eating habits are unchanged; once pathogens enter the interior, appetite is lost. Preference for cold drinks indicates internal heat (Neire). Preference for hot drinks indicates interior cold (Lihan). Symptoms that alleviate slightly after eating indicate deficiency (Xu). Symptoms that worsen after eating indicate excess (Shi). (Even in individuals with constitutionally deficient Qi, overeating can cause discomfort.) If the disease is caused by dietary indiscretion, one must ask what specific food was ingested improperly. Heat patterns invariably present with thirst, a preference for frozen beverages, and large volumes of intake. If one prefers hot drinks, or prefers cold drinks but consumes little, this is deficiency heat (Xure), not excess heat (Shire). (Those with Yang deficiency cannot tolerate cold drinks. Those with Yin deficiency may experience dryness due to fire scorching fluids, but drinking small amounts of cool, moistening liquids suffices because the root is deficiency, and the body cannot withstand the cold nature of water, hence they cannot drink much.)
Incontinence of both urine and feces indicates failure of the Kidney (Shen). (The Kidneys open into the two yin passages [anterior and posterior orifices]; when Kidney essence fails, it loses its function of securing the Zang organs.) Urine that is clear, white, and copious is definitely not a Heat pattern. (Note: There are cases where Fire resides in the Upper Jiao; if guided downward, the urine may turn yellow.) Urine that is yellow-red and scanty indicates Heat. However, exhaustion generating Fire, excessive worry stirring Fire, dysentery depleting Yin, or Internal Heat due to Yin Deficiency can all result in yellow urine. Although these represent Heat, they are Deficiency Heat (Xure), not Excess Heat (Shire). The generation and excretion of Body Fluids (Jinye) depend on Qi transformation (Qihua); Qi pathology leads to difficult urination. When Qi escapes upward, there will be no urine. When Qi is obstructed, there will also be no urine. Hardness and pain in the lower abdomen with difficulty in urination is termed Niase (dysuria/obstructed urination). Frequent passage of black stool indicates Accumulated Blood (Xuxue). Diarrhea accompanied by abdominal fullness is a critical condition (death prognosis). Constipation with hard, full abdomen and severe pain that cannot be pressed indicates Heat Binding (Rejie). Diarrhea is generally Cold, but can also be Heat, as stated in the classics: "Sudden violent diarrhea belongs to Heat." (The nature of Fire is rapid; food does not have time to transform before being expelled. The urgency is intense, with loud borborygmi, resembling crab foam. If Heat leaves with the diarrhea and Pain subsides with the relief, it may resolve spontaneously.) Another presentation is pure watery diarrhea, termed Rejie Pangliu (Heat binding with peripheral flow). (Dry fecal matter forms pellet-like masses inside, blocking waste, allowing only clear fluid to leak from the sides; the odor is extremely foul.) All these are Heat patterns. Additionally, duck-egg-consistency loose stools indicate Cold. Stool resembling moldy soybean paste, sticky (lacking visible undigested particles due to thermal digestion), and extremely foul-smelling indicates Heat.