It is unlikely that man, as we know him, would have survived without the
fictive, counter-factual, anti-determinist means of language, without the
semantic capacity, generated and stored in the 'superfluous' zones of the
cortex, to conceive of, to articulate possibilities beyond the treadmill of or-
ganic decay and death.^3The manufacture of "subjunctive worlds" happens so casually, so
naturally, that we hardly notice what we are doing. We select from our
fantasy a world which is close, in some internal mental sense, to the real
world. We compare what is real with what we perceive as almost real. In so
doing, what we gain is some intangible kind of perspective on reality. The
Sloth is a droll example of a variation on reality-a thinking being without
the ability to slip into subjunctives (or at least, who claims to be without the
ability-but you may have noticed that what he says is full of counterfactu-
als!). Think how immeasurably poorer our mental lives would be if we
didn't have this creative capacity for slipping out of the midst of reality into
soft "what if" 'sl And from the point of view of studying human thought
processes, this slippage is very interesting, for most of the time it happens
completely without conscious direction, which means that observation of
what kinds of things slip, versus what kinds don't, affords a good window
on the unconscious mind.
One way to gain some perspective on the nature of this mental metric
is to "fight fire with fire". This is done in the Dialogue, where our "subjunc-
tive ability" is asked to imagine a world in which the very notion of
subjunctive ability is slipped, compared to what we expect. In the Dialogue,
the first subjunctive instant replay-that where Palindromi stays in
bounds-is quite a normal thing to imagine. In fact, it was inspired by a
completely ordinary, casual remark made to me by a person sitting next to
me at a football game. For some reason it struck me and I wondered what
made it seem so natural to slip that particular thing, but not, say, the
number of the down, or the present score. From those thoughts, I went on
to consider other, probably less slippable features, such as the weather
(that's in the Dialogue), the kind of game (also in the Dialogue), and then
even loonier variations (also in the Dialogue). I noticed, though, that what
was completely ludicrous to slip in one situation could be quite slippable in
another. For instance, sometimes you might spontaneously wonder how
things would be if the ball had a different shape (e.g., if you are playing
basketball with a half-inflated ball); other times that would never enter your
mind (e.g., when watching a football game on TV).Layers of StabilityIt seemed to me then, and still does now, that the slippability of a feature of
some event (or circumstance) depends on a set of nested contexts in which
the event (or circumstance) is perceived to occur. The terms constant,
parameter, and variable, borrowed from mathematics, seem useful here.
Often mathematicians, physicists, and others will carry out a calculation,
saying "c is a constant, p is a parameter, and v is a variable". What they
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