"That is a recognition of a subject which is conversant about the Ego: "That is a presentment of activity which manifests blue and the rest." Over and above, therefore, the complement of subject-recognitions, let it be understood that there is an external object world perceptible, which is the cause of presentments of activity; and that this external world does not rise into being only from time to time on occasion of presentments resulting from ideation. According to the view of the Sensationalists (_vijñánavádin_), ideation is a power of generating such and such sensations (or presentments of activity) in subject-recognitions which exist as a single stream. The maturescence of this power is its readiness to produce its effect; of this the result is a presentment (or sensation); the antecedent momentary object (sensation) in the mental train is accepted as the cause, no other mental train being admitted to exercise such causality. It must therefore be stated that all momentary objects (fleeting sensations) in the subject-consciousness are alike able to bring about that maturescence of ideation in the subject-consciousness, which maturescence is productive of presentments of activity. If any one (of these fleeting sensations) had not this power, none would possess it, all existing alike in the stream of subject-recognitions. On the supposition that they all have this power, the effects cannot be diversified, and therefore any intelligent man, however unwilling, if he has a clear understanding, must decide, without putting out of sight the testimony of his consciousness, that to account for the occasional nature (of sense percepts) the six cognitions of sound, touch, colour, taste, and smell, of pleasure, and so forth, are produced on occasion of four conditions. These four conditions are known as (1.) the data, (2.) the suggestion, (3.) the medium, and (4.) the dominant (organ). Of these, the form of blue or the like arises from the condition of blue data in the understanding in which there is a manifestation of blue or the like, which manifestation is styled a cognition. The resuscitation of forms or cognitions arises from suggestion as a condition. The restriction to the apprehension of this or that object arises from the medium, light, for instance, as a condition, and from the dominant, the eye, for example, as another condition. The eye, as determinant of one particular cognition (form) where taste, &c., might have been equally cognised, is able to become dominant; for in everyday life he who determines is regarded as dominant. We must thus recognise four causes of pleasure and the rest which constitute the understanding and its modifications.