Guna
The "qualities" that describe everything in Ayurveda: 20 attributes of matter (heavy, light, hot…) and 3 qualities of the mind (sattva, rajas, tamas).
Guna literally means "quality" or "attribute" — and, in an older sense, "cord" or "thread", like the strands that weave reality together. It is Ayurveda’s fundamental descriptive tool: rather than analysing the chemical composition of a food or a season, the tradition describes them through their perceptible qualities.
The term covers two complementary systems. First, the 20 gunas of matter, organised into ten pairs of opposites: heavy/light, hot/cold, oily/dry, stable/mobile, and so on. Every dosha, every food, every climate has its own profile of qualities — Vata is light, dry and mobile; ghee is heavy, oily and cold. Then come the 3 gunas of the mind, inherited from Samkhya philosophy: sattva (clarity), rajas (agitation) and tamas (inertia), which describe mental states and even the character of foods.
This vocabulary is not decorative: it underpins the whole of Ayurvedic therapeutics. The great Ayurvedic principle — like increases like, opposites bring balance — is expressed entirely in gunas. A concrete example: a person with excess Vata (light, dry, cold, mobile) will be soothed by the opposite qualities — a warm, oily, heavy porridge, a steady routine — and aggravated by cold raw food and unpredictable days.
To see this reasoning in action, read what is a dosha and, on the plate, our guide to sattvic, rajasic and tamasic foods.