§35. =The Connections of Mental Processes.=—So far as the elementary processes are concerned, this question has already been answered in our discussion of perception. We found that there were _two modes of sensory connection_, two ways in which sensations may go together. In qualitative perceptions, such as the perception of a musical note, there is a blend or =fusion= of qualities; we can, to be sure, analyse the compound tone, after practice, into fundamental and overtones; yet it still comes to us as unitary, as a single impression; it stands only at one remove, so to speak, from the simplicity of sensation itself. The tastes of coffee and lemonade, with their blending of taste and smell, of touch and temperature; the organic feels of hunger and thirst and nausea; the kinæsthesis aroused by grasping and pulling, by lifting the arm and swinging the foot; all these experiences are fusions, more or less intimate, more or less complex, of sensory qualities. They too can be analysed; but the analysis is not easy; the qualities cling together, seem in a way to merge into one another. In spatial perceptions, on the other hand, in such perceptions as the sight of my desk with its litter of writing materials, the elementary processes stand out side by side; brown contrasts with blue, dark with light; here, we might say, is no confluence, but rather concourse. In the perception of rhythm we have the same separateness of sensations, only that it is now temporal instead of spatial; and in the perception of change (p. 132) we find both modes of connection, separate qualities or intensities passing into one another by that peculiar blur or fusion which we have called the index of change. This second type of connection, whether it is the side-by-side of space or the end-to-end of time, may be named =conjunction=. The associative tendencies which we have been more recently discussing are set up by series of meaningless syllables, that is to say, by discrete stimuli. It is clear, then, that the connection of the correlated mental processes is of the conjunctive type; we have said nothing of the brain-processes which underlie sensory fusion. We can, indeed, say nothing of them; we have no knowledge of their nature. It has been suggested that qualitative perception is correlated with a _synergy_ of the brain-processes, that is, with a cooperation so close that every process taking part in it loses something of its individuality. That is possible; we cannot say more.