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Similarly--and this is the fundamental implication of the Multiple Drafts model--if one wants to settle on some moment
of processing in the brain as the moment of consciousness, this has to be arbitrary. One can always "draw a line" in the
stream of processing in the brain, but there are no functional differences that could motivate declaring all prior stages
and revisions unconscious or preconscious adjustments, and all subsequent emendations to the content (as revealed by
recollection) to be post-experiential memory-contamination. The distinction lapses at close quarters.
Another implication of the Multiple Drafts model, in contrast to the Cartesian Theater, is that there is no need--or
room--for the sort of "filling in" suggested by frames C and D of figure 4. Discussing Kolers' experiment, Goodman
notes that it
"seems to leave us a choice between a retrospective construction theory and a belief in clairvoyance" (1978, p.83) What
then is "retrospective construction"?
Whether perception of the first flash is thought to be delayed or preserved or remembered [our italics], I call this the
retrospective construction theory--the theory that the construction perceived as occurring between the two flashes is
accomplished not earlier than the second.
It seems at first that Goodman does not choose between a Stalinesque theory (perception of the first flash is delayed)
and an Orwellian theory (the perception of the first flash is preserved or remembered), but his Orwellian revisionist
does not merely adjust judgments; he constructs material to fill in the gaps:
each of the intervening places along a path between the two flashes is filled in . . . with one of the flashed colors rather
than with successive intermediate colors. (p.85)
What Goodman overlooks is the possibility that the brain doesn't actually have to go to the trouble of "filling in"
anything with "construction", for no one is looking. As the Multiple Drafts model makes explicit, once a discrimination
has been made once, it does not have to be made again; the brain just adjusts to the conclusion that is drawn, making
the new interpretation of the information available for the modulation of subsequent behavior. Recall the Commander
in Chief in Calcutta; he just had to judge that the truce came before the battle; he didn't also have to mount some sort of
pageant of "historical reconstruction" to watch, in which he receives the letters in the "proper" order.
Similarly, when Goodman (1978) proposes that "the intervening motion is produced retrospectively, built only after the
second flash occurs and projected backwards in time," this suggests ominously that a final film is made and then run
through a magical projector whose beam somehow travels backwards in time onto the mind's screen. Whether or not
this is just what Van der Waals and Roelofs (1930) had in mind when they proposed "retrospective construction," it is
presumably what led Kolers (1972, p.184) to reject their hypothesis, insisting that all construction is carried out in "real
time." Why, though, should the brain bother to "produce" the "intervening motion"? Why not just conclude that there
was intervening motion, and encode that "retrospective" content into the processing stream? This would suffice for it to
seem to the subject that intervening motion had been experienced.
Our Multiple Drafts model agrees with Goodman that retrospectively the brain creates the content (the judgment) that
there was intervening motion, and this content is then available to govern activity and leave its mark on memory. But
our model claims that the brain does not bother "constructing" any representations that go to the trouble of "filling in"
the blanks. That would be a waste of time and (shall we say?) paint. The judgment is already in, so the brain can get on
with other tasks! Endnote 8
Goodman's "projection backwards in time," like Libet's "backwards referral in time," is an equivocal phrase. It might
mean something modest and defensible: a reference to some past time is included in the content. On this reading it
could be a claim like "This novel takes us back to ancient Rome . . ," which almost no one would interpret in a
metaphysically extravagant way, as claiming that the novel was some sort of time travel machine. This is the reading
that is consistent with Goodman's other views, but Kolers apparently took it to mean something metaphysically radical:
that there was some actual projection of one thing at one time to another time. As we shall see, the same equivocation
bedevils Libet's interpretation of his phenomena.
The model of the Cartesian Theater creates artifactual puzzle questions that cannot be answered, whereas for our model
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