The 9-Constitution Framework: Why One Diet Doesn't Fit All
Every few years, a new diet sweeps through the wellness world and claims to be THE answer. Keto. Paleo. Vegan. Carnivore. Intermittent fasting. Each has passionate advocates and dramatic before-and-after photos — and each fails for a large percentage of people who try it. Why? Because a diet is not a medicine that works the same for everyone; it's a tool whose effect depends entirely on the body wielding it. Traditional Chinese Medicine has known this for over two thousand years. Instead of asking 'what is the best diet?', TCM asks a far more useful question: 'what is the best diet FOR YOU, right now?' The answer comes from a system called the 9-Constitution classification (Jiu Ti Zhi), a standardized framework that describes nine baseline body states based on the balance of Qi, Blood, Yin, Yang, and fluids. The Balanced constitution is the rare ideal — flexible, resilient, rarely sick. The other eight are imbalance patterns: Qi Deficient (easily fatigued), Yang Deficient (always cold), Yin Deficient (dry and overheated), Phlegm-Damp (heavy and congested), Damp-Heat (oily and inflamed), Blood Stasis (stagnant and achy), Qi Stagnation (tense and melancholy), and Special Constitution (allergic and sensitive). Here's the point that changes everything: your constitution determines how your body responds to food. A warming, high-fat, low-carb diet like keto is medicine for a Damp-Heat person drowning in phlegmy heaviness — but it's poison for a Yin-Deficient person whose body is already dry, hot, and running on fumes. Raw salads that detox one person will bloat a Yang-Deficient person into misery. The same bowl of oatmeal that energizes a Qi-Deficient person makes a Damp person feel like concrete is setting in their stomach. Modern nutrition science is arriving at the same conclusion from a different direction: the 2018 'Personalized Nutrition' landmark studies (Zeevi et al., Cell) showed that identical meals produce dramatically different blood-sugar responses in different individuals — proving that one-size-fits-all dietary advice is scientifically indefensible. TCM's 9-constitution system is the original personalized nutrition: a two-thousand-year-old framework that matches food energetics to your body's baseline state. The goal of this article is simple: help you identify your constitution with a self-test, then give you the exact food rules for your type — what to emphasize, what to avoid, and what a day of eating looks like.
- Constitutions describe tendencies, not verdicts. Most people have one dominant pattern plus traces of 1-2 others — treat the framework as a compass, not a cage.
- Your constitution can shift with season, stress, pregnancy, illness, and age. Re-test every 3-6 months.
- A 'wrong' food for your constitution isn't forbidden forever — it's a food to eat rarely, in small amounts, cooked properly, or only in its correct season.
"The sages treated disease by first examining the constitution of the patient — their strength or weakness, their fat or thinness, their yin or yang — and only then administering treatment."
How to Identify Your Constitution: The Self-Test
This scored checklist takes about five minutes. Read each cluster of three statements; give yourself 1 point for each statement that describes you most of the time (not just occasionally). At the end, the cluster with the highest score is your dominant constitution. If two clusters tie, you have a mixed constitution — read both sections and prioritize the one whose symptoms bother you most. CLUSTER 1 — BALANCED (Ping He Zhi): I have steady energy from morning to night; I rarely get sick and recover quickly; my digestion, sleep, and mood are generally stable and resilient. CLUSTER 2 — QI DEFICIENT (Qi Xu Zhi): I feel tired even after 8 hours of sleep; I get breathless after mild exertion or talking; I catch every cold that goes around and my voice is often soft or weak. CLUSTER 3 — YANG DEFICIENT (Yang Xu Zhi): My hands and feet are cold even in warm rooms; I'm sensitive to cold weather and need more layers than others; I have loose stools, low libido, and a general feeling of internal chill. CLUSTER 4 — YIN DEFICIENT (Yin Xu Zhi): I feel hot in my palms, soles, and chest, especially at night; my skin, lips, eyes, and throat feel dry; I have night sweats, scanty dark urine, and a thin or absent tongue coating. CLUSTER 5 — PHLEGM-DAMP (Tan Shi Zhi): My body feels heavy and my head feels foggy, especially after meals; I gain weight easily, especially around the belly; I have a thick tongue coating, sticky mouth, and often feel congested. CLUSTER 6 — DAMP-HEAT (Shi Re Zhi): My face and scalp get oily quickly and I'm prone to acne or rashes; I often have a bitter taste in my mouth and smelly breath or body odor; I have sticky stools that are hard to wipe clean, and I feel worse in hot, humid weather. CLUSTER 7 — BLOOD STASIS (Xue Yu Zhi): I bruise easily and have dark circles under my eyes; my skin has a dusky or dull tone, sometimes with spider veins; I have fixed, stabbing pains that feel worse with pressure or at night. CLUSTER 8 — QI STAGNATION (Qi Yu Zhi): I feel emotionally tense, sigh frequently, and feel worse under stress; I have a sensation of a lump in my throat that won't clear; my chest and flanks feel tight, and symptoms worsen with emotional upset. CLUSTER 9 — SPECIAL / ALLERGIC (Te Bing Zhi): I have allergies — to foods, pollen, dust, or medications; I get hives, eczema, or asthma attacks; I react strongly to things most people tolerate without issue. Scoring guide: 0-1 points overall suggests a Balanced constitution. A dominant cluster (2-3 points) identifies your main imbalance. High scores in several clusters mean your constitution is complex — start with the highest-scoring pattern, stabilize it with diet for 4-6 weeks, then re-assess the others.
- Take the test on a normal day, not during illness, a hangover, a stressful week, or the day after a huge meal — acute states distort the baseline.
- Ask someone who lives with you for their observations. Partners notice your cold hands, sighing, or afternoon slumps more objectively than you do.
- This self-test is a screening tool, not a diagnosis. For serious or persistent symptoms, see a licensed TCM practitioner for a proper pulse and tongue assessment.
"The tongue is the sprout of the Heart, the mirror of the internal organs. Its color, coating, and moisture reveal the state of Qi, Blood, Yin, Yang, and fluids."
Constitutions 1-3: Balanced, Qi Deficient, Yang Deficient
CONSTITUTION 1 — BALANCED (Ping He Zhi): Core signs: steady energy, sound sleep, normal appetite, rare illness, quick recovery, even temperament. This is the constitutional ideal — roughly 10-15% of the population, and most of us only glimpse it in our best seasons. Food rules: you're the only constitution with true freedom — eat a wide variety of whole foods across all five flavors (sour, bitter, sweet, pungent, salty) and all four natures (cold, cool, neutral, warm). Emphasize: seasonal vegetables, whole grains, moderate protein, minimal processed food. Avoid: nothing strictly — but even a Balanced person damages themselves with chronic excess: years of heavy alcohol, sugar, or deep-fried food will eventually pull you into an imbalance. Sample day: warm congee with egg and scallion for breakfast; a grain bowl with roasted vegetables and grilled fish at lunch; a light vegetable soup with a small portion of chicken for dinner. CONSTITUTION 2 — QI DEFICIENT (Qi Xu Zhi): Core signs: chronic fatigue, weak voice, shortness of breath, poor appetite, loose stools, pallid complexion, tongue with scalloped (tooth-marked) edges. Qi is the body's fuel and defense; deficiency means low fuel and low immunity. Food rules: eat warm, cooked, easily digested foods that tonify Qi — the Spleen is the 'root of postnatal Qi,' and it loves simplicity. Emphasize: congee and rice porridge, oats, sweet potato, pumpkin, carrots, chicken, beef, eggs, dates (red jujube), Chinese yam, astragalus in broths. Avoid: raw salads, cold smoothies, iced drinks, excessive dairy, greasy food, and large heavy meals — all of which tax a weak digestive system; also avoid bitter herbs and excessive coffee, which drain Qi. Sample day: chicken-congee with ginger for breakfast; warm quinoa or rice bowl with steamed vegetables and a soft-boiled egg for lunch; slow-cooked chicken and astragalus soup with rice for dinner. CONSTITUTION 3 — YANG DEFICIENT (Yang Xu Zhi): Core signs: cold hands and feet, aversion to cold, low energy with cold-type fatigue, loose stools, pale face, clear voluminous urine, poor libido. Yang is the body's metabolic fire; deficiency means the furnace is running low. Food rules: eat warming foods and cook everything thoroughly — never raw, never cold. Emphasize: lamb, chicken, venison, shrimp, ginger, garlic, scallions, leeks, cinnamon, black pepper, cloves, fennel, walnuts, oats, and warm spices in everything. Avoid: raw vegetables, salads, ice cream, iced drinks, watermelon, bananas, grapefruit, and anything straight from the refrigerator — cold food directly extinguishes Spleen Yang. Sample day: ginger-scallion congee with a fried egg for breakfast; braised lamb or chicken with root vegetables and rice for lunch; a warming broth with ginger, garlic, and winter squash for dinner, finished with cinnamon tea.
- For Qi Deficient types, smaller frequent meals beat three large ones — a weak Spleen processes small loads well and large loads poorly.
- For Yang Deficient types, cooking method is medicine: slow braises, soups, and stews add warmth that raw or lightly cooked food cannot.
- Ginger is the universal warming ally — add a few slices to congee, tea, or broth daily if you run cold.
"Qi is the commander of Blood. Where Qi moves, Blood follows; where Qi is deficient, all functions weaken. The Spleen is the root of postnatal Qi."
Constitutions 4-6: Yin Deficient, Phlegm-Damp, Damp-Heat
CONSTITUTION 4 — YIN DEFICIENT (Yin Xu Zhi): Core signs: feeling hot in palms/soles/chest, night sweats, dry skin-lips-eyes-throat, thirst with a preference for cold drinks, scanty dark urine, constipation, a red tongue with scanty coating, irritability. Yin is the body's cooling, moistening fluid; deficiency produces a dry heat that burns from within. Food rules: eat cooling, moistening foods that nourish Yin fluids — and above all, avoid anything that further dries or heats the body. Emphasize: duck, pork, tofu, eggs, milk, barley, millet, pears, apples, watermelon, cucumber, celery, asparagus, spinach, water chestnuts, goji berries, black sesame, mint, chrysanthemum tea. Avoid: lamb, beef in excess, chili, garlic, ginger in large amounts, alcohol, coffee, deep-fried food, and any low-carb/high-fat diet — the keto-style approach is uniquely damaging here, because it is warming and drying precisely where you are already dry and hot. Sample day: barley porridge with pear and goji berries for breakfast; steamed fish with cucumber salad and rice for lunch; duck or tofu soup with winter melon and mint for dinner, followed by chrysanthemum tea. CONSTITUTION 5 — PHLEGM-DAMP (Tan Shi Zhi): Core signs: heaviness in the body and limbs, brain fog, a head that feels wrapped in cotton, easy weight gain concentrated at the belly, thick tongue coating, sticky mouth, loose but heavy stools, feeling worse in humid weather. Dampness is like internal humidity — sluggish, heavy, congesting. Food rules: eat light, drying, aromatic foods that resolve dampness; cut the foods that manufacture it (sugar, dairy, refined carbs, excess fat). Emphasize: barley, corn, rye, adzuki beans, mung beans, radish, celery, watercress, bitter melon, scallion, garlic, cardamom, cumin, fennel, and small amounts of lean white fish or chicken. Avoid: sugar in all forms, dairy, wheat in excess, bananas, peanuts, greasy fried food, alcohol (especially beer), and late-night heavy meals. Sample day: barley congee with a pinch of cardamom for breakfast; a vegetable-heavy lunch with mung bean soup and brown rice; dinner of steamed white fish with bok choy and radish, no dessert. CONSTITUTION 6 — DAMP-HEAT (Shi Re Zhi): Core signs: oily face and scalp, acne and rashes, bitter taste in the mouth, bad breath, body odor, yellow-sticky discharge, sticky stools that smear, dark yellow urine, irritability, feeling worse in heat and humidity. Dampness combined with heat is like a steam bath — congested, inflamed, and stagnant. Food rules: eat cooling, drying, bitter foods that clear heat and drain dampness; this is the constitution where the keto-style and low-carb approaches genuinely help, because fat restriction plus reduced sugar dries the dampness. Emphasize: bitter melon, cucumber, celery, mung beans, adzuki beans, barley, corn, water chestnut, winter melon, lotus root, green tea, chrysanthemum tea, and bitter greens like dandelion and arugula. Avoid: alcohol, fried food, spicy food, sugar, dairy, red meat in excess, nuts in excess, and hot-dry foods like lamb and chili — these feed both the damp and the heat. Sample day: mung bean and barley porridge for breakfast; bitter greens stir-fried with garlic and a small portion of fish with rice for lunch; winter melon soup with lean pork for dinner, with green tea throughout the day.
- For Damp types, the simplest rule: if it's white, sweet, greasy, or fried, it's probably feeding your dampness. If it's green, bitter, light, or brothy, it's probably helping.
- For Yin Deficient types, hydration matters — not just water but moistening foods: soups, stews, pears, and cooked grains retain the moisture your body needs.
- Damp-heat types should watch alcohol and sugar together — they are the single worst combination for this constitution, especially beer and sweet cocktails.
"When dampness and heat combine, they are like wet firewood — the dampness binds the heat and the heat steams the dampness, producing congestion, discharge, and inflammation."
Constitutions 7-9: Blood Stasis, Qi Stagnation, Special (Allergic)
CONSTITUTION 7 — BLOOD STASIS (Xue Yu Zhi): Core signs: bruising easily, dark circles under the eyes, dusky or dull skin, spider veins, fixed stabbing pains worse at night, dark-purple tongue, and — in women — painful periods with dark clotted blood. Blood Stasis means circulation is sluggish and the blood is not moving freely. Food rules: eat foods that move blood, warm the channels, and thin the sludge; avoid foods that congeal. Emphasize: onions, garlic, chives, turmeric, ginger, cayenne in moderation, black pepper, eggplant, kelp, hawthorn berry (shan zha), vinegar, salmon, sardines, and dark leafy greens. Avoid: excessive sugar, trans fats, deep-fried food, ice-cold drinks (cold congeals blood), and a sedentary diet of heavy processed food — also minimize alcohol, which damages blood vessels over time. Sample day: warm oatmeal with hawthorn berry jam for breakfast; a lunch of grilled salmon with steamed greens and a vinegar-ginger dressing; dinner of eggplant and onion stir-fry with rice, plus a daily 20-minute walk — movement is food for stagnant blood. CONSTITUTION 8 — QI STAGNATION (Qi Yu Zhi): Core signs: emotional tension, frequent sighing, a sensation of a lump in the throat (plum-pit qi), chest and flank tightness, irritability, mood swings, symptoms that worsen with stress, and digestive complaints tied to emotion. Qi Stagnation means your energy flow is blocked — like a river dammed, pressure builds upstream. Food rules: eat foods that move Qi, relax tension, and support the Liver's free-flowing function; the Liver governs the smooth movement of Qi and emotions. Emphasize: mint, chamomile, rose tea, citrus peel (chen pi), radish, daikon, scallion, onion, garlic, celery, asparagus, buckwheat, and small amounts of alcohol-free 'moving' spices like turmeric and cardamom. Avoid: heavy greasy food that bogs Qi down, excessive caffeine that jangles the Liver, and — critically — emotional eating and rushed meals, which are the dietary version of Qi stagnation. Sample day: buckwheat porridge with a citrus note for breakfast; a lunch of steamed fish with radish and greens; dinner of vegetable soup with celery, scallion, and a pinch of turmeric, followed by rose or chamomile tea and a slow walk. CONSTITUTION 9 — SPECIAL / ALLERGIC (Te Bing Zhi): Core signs: allergies to foods, pollen, dust, or medications; hives, eczema, asthma, hay fever; strong reactions to things others tolerate; a tendency to be constitutionally sensitive. This is the 'allergic constitution' — the immune system overreacts to ordinary stimuli. Food rules: eat neutral, gentle, anti-inflammatory foods that steady the immune response; identify and strictly avoid personal triggers; keep the digestive barrier strong, because TCM holds that Spleen weakness underlies many allergies. Emphasize: rice, congee, gentle cooked vegetables, small amounts of clean protein, and calming foods like pumpkin, yam, cabbage, and warm broths; consider a food diary to map triggers precisely. Avoid: your known allergens, plus common aggravators that often co-occur — shellfish, peanuts, dairy, gluten — and foods high in histamine when you're reactive: aged cheese, cured meats, fermented foods, alcohol. Sample day: plain rice congee with a soft egg for breakfast; steamed chicken and vegetables with rice for lunch; a simple pumpkin and yam soup for dinner — a deliberately boring, gentle day that lets the immune system rest.
- For Blood Stasis, combine diet with movement — walking, qi gong, or tai chi daily. Stagnant blood cannot be fixed by food alone.
- For Qi Stagnation, eat slowly and calmly. Qi moves with breath and mood; a rushed, stressful meal creates stagnation no matter what's on the plate.
- For Special Constitution, keep a trigger journal: food, symptom, timing. Patterns emerge within 2-4 weeks and are worth more than any allergy panel.
"The Liver governs the free-flowing movement of Qi. When the Liver is harmonious, Qi flows smoothly and the emotions are at ease; when it stagnates, constraint gives rise to depression, sighing, and a lump in the throat."
The Constitution Cheat Sheet: One-Line Summary Per Type
Here's the whole framework on one page — the one-line summary, plus the food to load up on and the food to steer clear of for each of the 9 types. Bookmark this section. BALANCED (平和质): Eat everything in moderation; your only job is to not ruin a good constitution. Eat: all whole foods, all five flavors. Avoid: chronic excess of anything — sugar, alcohol, grease. QI DEFICIENT (气虚质): Warm, cooked, simple food builds your fuel; raw and cold food drains it. Eat: congee, oats, sweet potato, chicken, eggs, dates, Chinese yam. Avoid: raw salads, cold smoothies, iced drinks, heavy greasy meals. YANG DEFICIENT (阳虚质): You are a cold body — eat fire. Eat: lamb, chicken, ginger, garlic, cinnamon, leeks, walnuts, slow-cooked stews. Avoid: anything raw, cold, or straight from the fridge; watermelon, bananas, ice cream. YIN DEFICIENT (阴虚质): You are a dry, hot body — eat moisture and coolness. Eat: duck, tofu, barley, pears, cucumber, goji berries, mint, chrysanthemum tea. Avoid: chili, lamb, alcohol, coffee, deep-fried food, keto-style high-fat diets. PHLEGM-DAMP (痰湿质): You are an internal swamp — eat light, drying, aromatic food. Eat: barley, mung beans, adzuki beans, radish, celery, cardamom, scallion. Avoid: sugar, dairy, wheat in excess, bananas, peanuts, beer, greasy food. DAMP-HEAT (湿热质): You are a steam bath — eat cooling, bitter, draining food. Eat: bitter melon, cucumber, winter melon, mung beans, green tea, bitter greens. Avoid: alcohol, fried food, chili, sugar, dairy, red meat, hot-dry foods. BLOOD STASIS (血瘀质): Your blood moves too slowly — eat food that moves it. Eat: onions, turmeric, ginger, vinegar, hawthorn berry, salmon, dark greens. Avoid: ice-cold drinks, excess sugar, trans fats, deep-fried food, a sedentary diet. QI STAGNATION (气郁质): Your Qi is dammed up — eat food that frees the flow. Eat: mint, chamomile, rose tea, citrus peel, radish, celery, buckwheat, scallion. Avoid: heavy grease, excess caffeine, rushed meals, emotional eating. SPECIAL (特禀质): Your immune system overreacts — eat gentle, neutral food and know your triggers. Eat: rice congee, yam, pumpkin, cabbage, clean protein, warm broths. Avoid: personal allergens, shellfish, peanuts, dairy, gluten, high-histamine foods when reactive. Print this, stick it on the fridge, and let it guide every grocery run and restaurant order.
- The one-line summaries are the 'always' rules; the tables are the 'usually' rules. When in doubt, follow the one-liner.
- If you have a mixed constitution (most people do), start by fixing the dominant pattern — don't try to obey two conflicting sets of rules at once.
- Season adjusts the rules: a Yang-Deficient person still eats more cooling food in summer, and a Damp-Heat person can tolerate a little more warmth in winter.
"Treat according to the person, according to the season, and according to the locality. One who treats disease without regard for the individual is like one who fights a war without knowing the enemy."
Re-Testing and Adjustment: Constitutions Change with Seasons and Life Stages
A constitution is not a permanent identity — it's a snapshot of your body's baseline, and baselines shift. Re-test yourself with the checklist every season (every 3 months) and after major life events: pregnancy and postpartum, significant weight changes, prolonged illness, surgery, menopause, or intense stress. What you'll notice is that most people don't switch constitutions — they oscillate. A Qi-Deficient person becomes more Yang-Deficient after a hard winter. A Damp-Heat person slides toward Phlegm-Damp in a humid summer. A Balanced person dips into Qi Stagnation during a brutal work season. Your diet should track these shifts. Practical adjustment rules: in winter, everyone (even hot types) shifts toward warming foods — a Yin-Deficient person swaps cold salads for warm but still moistening soups. In summer, everyone shifts toward cooling foods — a Yang-Deficient person adds more cooked greens and light broths without ever going fully raw. At life stages: teenagers need nourishing growth foods; pregnant women tonify Blood and Qi; new mothers eat warming recovery soups (see our article on medicinal soups for the classics); and people over 60 — whose Spleen Qi naturally declines — eat smaller, warmer, more cooked meals with less raw food and less cold drink. The deeper principle is responsiveness: your body is talking to you all day long through energy, digestion, skin, mood, and sleep. The constitution framework gives you a language to hear it. When a food reliably makes you heavy, foggy, bloated, or irritable, that food is wrong for your current constitution — regardless of what any diet book says. When a food reliably gives you clean energy and easy digestion, that food is right. This is the original biofeedback, and it's far more accurate than any algorithm.
- Set a seasonal reminder to re-take the self-test — the equinoxes and solstices are natural check-in points.
- Track your dominant pattern over a year. Most people discover one 'home' constitution with predictable seasonal excursions.
- After stabilizing your dominant pattern for 6-8 weeks, re-test and address the secondary pattern — many people find the secondary one resolves on its own.
"The wise physician adapts treatment to the season: warm in spring, cool in summer, moistening in autumn, and warming-tonifying in winter, always following the rhythm of heaven and earth."
Common Mistakes: Mixing Constitutions, Over-Correcting, and Trend Diets vs Constitution Diets
Mistake 1 — Treating the framework as a buffet: People read all 9 sections and assemble a diet from whatever sounds appealing — a bit of the warming lamb, some of the cooling cucumber, the anti-inflammatory turmeric. The result is a nutritional mess that follows no constitution at all. You have one dominant pattern; build your diet around it, and let the secondary pattern only fine-tune the edges. Mistake 2 — Over-correcting: The opposite error is zealotry. A Yang-Deficient person who eliminates every 'cooling' food becomes rigid and fearful; a Damp-Heat person who lives on bitter melon and green tea alone destroys their appetite and Qi. Food therapy is a nudge, not a sledgehammer. Shift proportions by 20-30% toward your constitution's foods — don't rebuild your entire diet overnight, and never eliminate entire food groups without a practitioner's guidance. Mistake 3 — Confusing a constitution diet with a trend diet: Trend diets (keto, paleo, vegan, carnivore) are universal prescriptions — the same rules for everyone. Constitution diets are individual prescriptions — different rules for different bodies. The keto diet is not 'wrong'; it's wrong for some constitutions and right for others. Paleo isn't evil; it's actively harmful for a Blood-Deficient woman who needs nourishing carbohydrates. The moment you ask 'what does this diet do to MY constitution?' instead of 'is this diet good?', you graduate from dietary fashion to dietary medicine. Mistake 4 — Ignoring the tongue and pulse: Self-tests are excellent, but tongue and pulse diagnosis catches what questionnaires miss — especially in mixed and complex constitutions. If your symptoms are severe, persistent, or confusing, invest in one session with a licensed TCM practitioner: they'll read your constitution more precisely than any checklist, and the follow-up re-tests will confirm whether your diet is working. Mistake 5 — Expecting overnight results: Constitutional eating is a slow, cumulative medicine. In my practice, most people notice digestive improvements in 2-4 weeks, energy shifts in 4-8 weeks, and skin, weight, and mood changes over 2-3 months. The people who quit after ten days never meet their constitution. The people who stay for a season don't just change their diet — they change their relationship with food, from eating what the culture tells them to eating what their body tells them. That's the real transformation, and it's available to every one of the 9 constitutions.
- Pick ONE dominant constitution, follow its rules for 6 weeks, and evaluate. If symptoms improved, you identified correctly. If not, re-test — the secondary pattern may actually be primary.
- Change one meal at a time. Breakfast for two weeks, then lunch, then dinner. Sustainable shifts beat dramatic overhauls.
- When a trend diet tempts you, translate it: 'What is this diet's energetic signature — warming or cooling, drying or moistening? Is that what my constitution needs right now?'
"Medicine and food share the same origin. But what is medicine for one person is food for another, and what nourishes one constitution injures another."