2.9 Assumptions 65
Those who are fearful of the internet
should therefore stop worrying about its
dangers and acknowledge that, on
balance, its growth is in the public
interest, not against it. For, almost at a
stroke, it has given us freedom of
information on a scale that could never
previously have been imagined.Analyse the above argument so that you are
clear about its reasons and conclusion. Then
decide which of the following is a key
underlying but unstated assumption. (There
is only one correct answer.)
A There are some reasons to be worried
about the internet.
B Freedom of information is in the public
interest.
C The internet is here to stay.
D Everyone has the right to publish their
opinions.Activity
Commentary
In simplified form the argument runs as
follows:R Now anyone can express views publicly or
distribute information at little cost.IC The internet has given us freedom of
information on an unimaginable scale.C Those who are fearful of the internet
should . . . acknowledge that its growth is
in the public interest.
The first two sentences of the passage can be
interpreted either as background information
or as additional reasons to supplement the
sub-argument, from R to IC. Either way the
main argument is from IC to C. This step
works only if we assume that freedom of
information is itself in the public interest,evidence; A by common knowledge. Moreover,
A is arguably true by definition, since a ‘serial’
number means one number in a series.
Therefore, although [2] in its original form is
incomplete, when we add in the obvious
assumption, we see that what is intended is a
good and plausible argument.
Interestingly, the same conclusion could
have been reached by stating A and assuming R:
[3] Genuine banknotes would have different
serial numbers, so these notes can’t be
genuine.Again the single premise makes sense as a
reason for the conclusion only if it assumes
that some of the banknotes in question have
the same number. In [3] this is not stated, but
only because it does not need to be. We can
understand the argument perfectly well
without it.
Remember that, under the principle of
charity, we start from the presumption that
the author of an argument is as rational as we
are, and would not have left out a crucial
premise through carelessness or stupidity, but
would have meant it to be taken as read.
Identifying implicit assumptions
In the examples we have examined so far it
would be very difficult not to recognise the
implicit assumptions. But with longer and
more complex arguments it can require careful
and thorough analysis. Consider, for example,
the following passage:
[4] In the days before the arrival of the
internet, publishers and booksellers
effectively controlled what people read,
since very few would-be authors could
afford the high financial risks of
publishing themselves. The internet
has changed all that, with Facebook and
Twitter leading the charge. Now anyone
can express their views publicly, or
distribute information, at little or no cost,
and without the tyranny of censorship.