If we contemplate even a minute sector of life's vast range, we are faced with a variety of living forms so tremendous that it defies all description. Yet three basic features can be discerned as common to everything that has animate existence, from the microbe to man, from the simplest sensations to the thoughts of a creative genius:
impermanence or change (anicca);
suffering or unsatisfactoriness (dukkha);
non-self or insubstantiality (anatta).
These three basic facts were first found and formulated over 2,500 years ago by the Buddha, who was rightly called "the Knower of the World" (loka-vidu). They are designated, in Buddhist terminology, the three characteristics (ti-lakkhana) — the invariable marks or signs of everything that springs into being, the "signata" stamped upon the very face of life itself.
Of the three, the first and third apply directly to inanimate existence as well as to the animate, for every concrete entity by its very nature undergoes change and is devoid of substance. The second feature, suffering, is of course only an experience of the animate. But the Buddha applies the characteristic of suffering to all conditioned things, in the sense that, for living beings, everything conditioned is a potential cause of experienced suffering and is at any rate incapable of giving lasting satisfaction. Thus the three are truly universal marks pertaining even to what is below or beyond our normal range of perception.
The Buddha teaches that life can be correctly understood only if these basic facts are understood. And this understanding must take place, not only logically, but in confrontation with one's own experience. Insight-wisdom, which is the ultimate liberating factor in Buddhism, consists in just this experiential understanding of the three characteristics as applied to one's own bodily and mental processes, and deepened and matured in meditation.
To see things as they really are means to see them consistently in the light of the three characteristics. Not to see them in this way, or to deceive oneself about their reality and range of application, is the defining mark of ignorance, and ignorance is by itself a potent cause of suffering, knitting the net in which man is caught — the net of false hopes, of unrealistic and harmful desires, of delusive ideologies and of perverted values and aims.
Ignoring or distorting the three basic facts ultimately leads only to frustration, disappointment and despair. But if we learn to see through deceptive appearances, and discern the three characteristics, this will yield immense benefits, both in our daily life and in our spiritual striving. On the mundane level, the clear comprehension of impermanence, suffering and non-self will bring us a saner outlook on life. It will free us from unrealistic expectations, bestow a courageous acceptance of suffering and failure, and protect us against the lure of deluded assumptions and beliefs. In our quest for the supramundane, comprehension of the three characteristics will be indispensable. The meditative experience of all phenomena as inseparable from the three marks will loosen, and finally cut, the bonds binding us to an existence falsely imagined to be lasting, pleasurable and substantive. With growing clarity, all things internal and external will be seen in their true nature: as constantly changing, as bound up with suffering and as unsubstantial, without an eternal soul or abiding essence. By seeing thus, detachment will grow, bringing greater freedom from egoistic clinging and culminating in Nibbana, mind's final liberation from suffering.