The ancient teachers of the Abhidhamma illustrate the cognitive process occurring in the sense doors with the simile of the mango. A certain man with his head covered went to sleep at the foot of a fruiting mango tree. Then a ripe mango loosened from the stalk fell to the ground, grazing his ear. Awakened by the sound, he opened his eyes and looked; then he stretched out his hand, took the fruit, squeezed it, and smelt it. Having done so, he ate the mango, swallowed it appreciating its taste, and then went back to sleep.

Here, the time of the man's sleeping at the foot of the mango tree is like the time when the bhavanga is occurring. The instant of the ripe mango falling from its stalk and grazing his ear is like the instant of the object striking one of the sense organs, for instance, the eye. The time of awaking through the sound is like that of the five-door adverting consciousness turning towards the object. The time of the man's open­ing his eyes and looking is like eye-consciousness accomplishing its function of seeing. The time of stretching out his hand and taking the mango is like that of the receiving consciousness receiving the object. The time of squeezing the fruit is like that of the investigating con­sciousness investigating the object. The time of smelling the mango is like that of the determining consciousness determining the object. The time of eating the mango is like that of javana experiencing the flavor of the object. The swallowing of the fruit while appreciating its taste is like the registration consciousness taking the same object as the javana phase. And the man's going back to sleep is like the subsidence back into the bhavanga.

It should be noted that the entire cognitive process occurs without any self or subject behind it as an enduring experiencer or inner con­troller, a "knower" outside the scope of the process itself. The momen­tary cittas (consciousness) themselves exercise all the functions necessary to cognition, and the unity of the cognitive act derives from their coordination through laws of conditional connectedness. Within the cognitive process each citta comes into being in accordance with the lawful order of con­sciousness (cittaniydma). It arises in dependence on a variety of condi­tions, including the preceding citta, the object, a door, and a physical base. Having arisen, it performs its own unique function within the process, and then it dissolves, becoming a condition for the next citta.

Source: A Comprehensive Manual of Abhidhamma (Buddhist Publication Society, 1993)