Theism and Explanation - Appeared-to-Blogly

126 Theism and Explanation
7.2 BACKGROUND KNOWLEDGE
A second desideratum for any explanation has to do with its relationship to
our background knowledge. What I wish to argue is that consistency with
background knowledge is an explanatory virtue, one that should contribute
to our willingness to accept a proposed explanation. And proposed theistic
explanations are no exception to this rule. They will score poorly when
measured against this criterion, precisely because the agent they posit is so
dissimilar to any other with which we are familiar.
But fi rst, what do I mean by “background knowledge”? Background
knowledge is best thought of as those facts of which we are aware independently
of the explanation in question. More precisely, it consists of all
the propositions we have reason to regard as true other than the proposed
explanans. But we should also exclude from background knowledge the
fact we are trying to explain, for to appeal to the explanandum in support
of the explanans is to ask about the latter’s explanatory force. It is to ask
whether the hypothesis is, in fact, a potential explanation of the fact to be
explained. And that is a prior question to the one I am asking here, which
I dealt with in Chapter 6. The point I am making here is this: When the
mechanisms posited by potential explanation are consistent with what we
already know about the world, this can (and should) contribute to our willingness
to accept it. And when they are not consistent with what we already
know about the world, this gives us a reason to treat it with suspicion.
Background knowledge, so defi ned, includes successful theories. The
point I am making here is that we should (other things being equal) prefer
those proposed explanations that are consistent with what we already
know about the world. And this means they are consistent not only with
observable facts, but also with our best existing theories. One could apparently
explain the operation of electric light bulbs (and even candles) by
proposing that they “suck dark” rather than “emit light.”
Take for example, the dark suckers in the room where you are. There
is less dark right next to them than there is elsewhere. The larger the
dark sucker, the greater its capacity to suck dark. Dark suckers in a
parking lot have much greater capacity than the ones in this room. As
with all things, dark suckers don’t last forever. Once they are full of
dark, they can no longer suck. This is proven by the black spot on a
full dark sucker. A candle is a primitive dark sucker. A new candle has
a white wick. You will notice that after the fi rst use, the wick turns
black, representing the dark which has been sucked into it. If you hold
a pencil next to the wick on an operating candle, the tip will turn
black, because it got in the way of the dark fl owing into the candle.
Unfortunately, these dark suckers have a very limited range. There are
also portable dark suckers. The bulbs in these units can’t handle all
of the dark by themselves, and must be aided by a dark storage unit.
When the dark storage unit is full, it must be either emptied or replaced