  If this reasoning is sound, it looks as though we have good reason for preferring the Retentional model to the Extensional alternative. However, there are replies available to the Extensionalist. One option is to hold grant that phenomenal contents are essentially (subjectively) dynamic, but hold that the briefest genuine episodes of experiencing in a specious present (or stream of consciousness) have a finite temporal extension; on this view momentary cross-sections of a stream of consciousness are no more than abstractions. A second option is to reject the claim that phenomenal contents are essentially dynamic. We may not be able to imagine experiential contents that are entirely static, but this doesn’t mean they are not possible: perhaps our imaginations are incapable of recreating all possible modes of experience. A third, and more intriguing option, is to accept that experience is essentially dynamic, and also accept that a stream can decompose into ever briefer parts, but reject the assumption that this decomposition must terminate in durationless episodes of experience. An alternative possibility is that the decomposition continues indefinitely – to infinity – without ever terminating in durationless point-like parts. In contemporary parlance, perhaps consciousness has the structure of atomless gunk. This species of gunk is a sort of stuff that is infinitely divisible, but not possessing point-like parts: all the parts of a portion of gunk have proper parts, without end. Whitehead and Broad were of the view that ordinary space and time possessed this structure. Irrespective of whether they were right about this, it may be that our streams of consciousness have this structure. If so, then they can possess an infinite number of parts, all of which have some (usually very brief) duration, and each of these parts may have a dynamic content. Wherever the truth lies on this issue, the temporal microstructure of experience looks to be fertile ground for Extensionalist exploration.