200 Unit 4 Applied critical thinking
that dolphins are like people. It just says that it
adds more evidence for such a view. However,
by saying that it adds more evidence, there is a
new assumption that some such evidence
already exists. If it doesn’t, then on its own the
evidence of tail-walking looks even weaker.Flaws
You were also asked whether any flaws or
fallacies can be found in the reasoning. There
are several possible candidates, but we will
concentrate for now on just one part of the
document, namely the last two paragraphs.
Here we have Dr Bossley’s claim that: ‘“As far
as we are aware, tail-walking has no practical
function and is performed as some form of
recreation, like human dancing or
gymnastics.”’ Firstly, this carries the
implication that if something has no practical
purpose, then it has to be recreational, which
could be seen as an example of restricting the
options (see Chapter 4.7). There may be other
possible explanations for the behaviour
besides these two. However, if you think that
all acts are either functional or recreational,
then it is legitimate to imply this.
But there is arguably a more serious fault
here. It is using Dr Bossley’s claim as evidence
for the contention that dolphins are ‘so
similar to humans that they are worthy of a
special ethical status.. .’. ‘Recreations’,
especially activities such as dancing and
gymnastics, are distinctively human. We don’t
know if animals do anything that resembles
our sporting or artistic pastimes; so it is a
major assumption to suppose dolphins do,
especially in the context of arguing for
similarities between dolphins and humans.
This lays the argument open to the charge of
begging the question. How can we justify the
claim that tail-walking is ‘like human dancing’
without assuming that there is something
human about dolphin behaviour? But that is
the very issue that the argument is about.
(Note that ‘question’ in this context should be
understood as what is at issue, and not as an‘non-human persons’? On one reading it is
almost contradictory: What is a person if it is
not human? On another reading, it could just
mean an animal anyway. If the status of
non-human persons differs from that of
humans and from that of other animals, we
need to know what it is. No conclusion can be
fully justified unless it is clear exactly what is
being argued for. (There is an important lesson
here for question (c) when we come to it.)Assumptions
As with many arguments, the problem with
the reasoning in this passage can be put down
to a major assumption that the author makes.
In drawing the conclusion, the author
assumes that an animal’s behaviour is a
reliable indicator of its intelligence, and/or of
its thoughts or feelings. Perhaps this is a
reasonable assumption. But it is an
assumption nonetheless: there is no
independent support for it.
This assumption is not explicitly stated in
the text. However, it is implicit, meaning that
even though the author doesn’t state it, it
must be true for the conclusion to follow from
the premises. We can put this to the test by
seeing what effect it would have on the
argument if we denied the assumption. If it
were false that observed behaviour can tell us
anything about inner processes or human-like
feelings, then the observation of tail-walking
becomes worthless as evidence that dolphins
are intelligent, or that they are performing the
act for ‘fun’, or ‘teaching’ each other. They
may appear to be, as stated; but if appearances
count for nothing, these observations are not
evidence at all.
On the other hand, if you consider that the
assumption is warranted, and that their
behaviour is a reliable indicator of what
dolphins experience, then you may feel that
this argument does have some strength. One
important point in its favour is that the
conclusion itself is not overstated. It does not
declare that tail-walking is some kind of proof