three categories of illusion ［三惑］ ( san-waku): Also, three illusions. A classification of illusions, established by T’ien-t’ai (538–597): (1) illusions of thought and desire, (2) illusions innumerable as particles of dust and sand, and (3) illusions about the true nature of existence. The illusions of thought and desire are illusions to be eradicated by persons of the two vehicles (voice-hearers and cause-awakened ones) and bodhisattvas. The other two categories of illusions are those that bodhisattvas alone go on to eliminate.
Illusions of thought and desire cause people to suffer in the six paths and the threefold world. Illusions of thought are distorted perceptions of the truth and are primarily mental and learned. They consist of the five false views and the five delusive inclinations. The five false views are as follows: (1) Though the body is nothing but a temporary union of the five components, one mistakenly thinks of the self as a separate or independent entity, and though nothing in the universe can belong to an individual, one mistakenly views that which surrounds one as one’s own possession. (2) One erroneously believes either that life is totally annihilated at death without continuance in any form, or that life persists after death in some eternally unchanged form such as a soul. (3) One does not recognize the law of cause and effect. (4) One adheres to misconceptions such as regarding inferior things as superior. (5) One views erroneous precepts or practices as the true way to enlightenment. The five delusive inclinations are greed, anger, foolishness, arrogance, and doubt; they arise in relation to the five false views. Hence in the category of illusions of thought, the five false views are regarded as primary and the five delusive inclinations as secondary. In contrast to the chiefly mental illusions of thought, the illusions of desire are emotional and inborn. These include greed, anger, foolishness, and arrogance and arise in connection with the various affairs and phenomena of the threefold world, not because of distorted perceptions of the truth.
Illusions innumerable as particles of dust and sand are illusions that prevent bodhisattvas from saving others. To save others, bodhisattvas must be well versed in innumerable teachings, both religious and secular. This second category of illusions arises when the bodhisattvas try to master these teachings.
Illusions about the true nature of existence are illusions that prevent bodhisattvas from attaining enlightenment, or from awakening to the truth of the Middle Way. In the specific teaching, these illusions are divided into twelve. In the perfect teaching, they are divided into forty-two, the last and most deeply rooted of which is called fundamental darkness. By eliminating fundamental darkness, one attains Buddhahood. In Great Concentration and Insight, T’ien-t’ai states that the three categories of illusion are eliminated through meditation aimed at perceiving the unification of the three truths in a single mind. Specifically, the illusions of thought and desire are eliminated by perception of the truth of non-substantiality; illusions innumerable as particles of dust and sand are eliminated by perception of the truth of temporary existence; and illusions about the true nature of existence are eliminated by perception of the truth of the Middle Way.