 By contrast, the second way of understanding the relation between the parts of the active intellect and the active intellect as a whole would be to use the analogy of the relation between the parts of a clock and the clock as a whole. Here, we have in fact different kinds of activities. But, as Taurellus argues, the difference between the activities of the parts of a clock is exactly what justifies regarding these parts as separate entities of a different kind. Analogously, what speaks in favor of regarding human minds as separate substances is not just the fact that reflexive acts occur but also that the content of one series of reflexive acts is not accessible from the perspective of another series of reflexive acts (AC: 271). The cognitive inaccessibility of one series of reflexive acts from the perspective of another series of reflexive acts would thus be inexplicable when one assumes, as Cesalpino does, that these acts derive from a unique intelligence. This is why Taurellus believes that the structure of reflexive acts speaks in favor of the existence of a plurality of active substances.