1. Translated from the Visuddhi-Magga (chap. iii.)
WHAT is concentration? Concentration is manifold and various, and an answer which attempted to be exhaustive would both fail of its purpose and tend to still greater confusion. Therefore we will confine ourselves to the meaning here intended, and sayConcentration is an intentness of meritorious thoughts.
Whenever, O priests, a priest, having isolated himself from sensual pleasures, having isolated himself from demeritorious traits, and still exercising reasoning, still exercising reflection, enters upon the first trance, which is produced by isolation and characterized by joy and happiness; when, through the subsidence of reasoning and reflection, and still retaining joy and happiness, he enters upon the second trance, which is an interior tranquilization and intentness of thoughts, and is produced by concentration; when, through the paling of joy, indifferent, contemplative, conscious, and in the experience of bodily happinessthat state which eminent men describe when they say, Indifferent, contemplative, and living happilyhe enters upon the third trance; when, through the abandonment of happiness, through the abandonment of misery, through the disappearance of all antecedent gladness and grief, he enters upon the fourth trance, which has neither misery nor happiness, but is contemplation as refined by indifference, this, O priests, is called the discipline in elevated concentration.