The previous chapter started off with phenomenological considerations about time or, to be a little more specific, about what one might call experiential or perceptual time. Toward the end of the chapter I hinted at several issues and details where a fruitful interaction and mutual enrichment between phenomenology and neuroscience, especially with respect to the concepts of retention and protention, seems possible. This, however, immediately raises questions about the underlying concept (or even concepts?) of time. On the one hand, the kind or type of temporal order in which the aforementioned brain responses are measured is induced by the direct application of electrodynamics and may be called physical time. On the other hand, the kind of order described by the phenomenologist is that of perceptual time. And the exact relationship between these two types of temporal order is not immediately obvious. At least some characteristics of the physiologically relevant temporal relations as measured by a clock seem different from the phenomenologically relevant, experienced temporal relations which are genuinely directed toward the immediate past and future (see Hua III: 196–7).