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The Expression of the Emotions in Man and Animals by Charles Darwin, edited
by Paul Ekman, HarperCollins, 拢16.99, ISBN 0002558661

YOU might reasonably be forgiven for thinking that human evolutionary biology
is a second-rate science. One has only to turn on the radio or open a newspaper
to find someone claiming that this or that aspect of human behaviour might have
been the result of selection on Stone Age people for this or that reason. Often
it seems that plausibility alone is grounds for accepting a hypothesis. Where
are the data and where are the tests?

It is a mistake, however, to suppose that the apparent lack of rigour
displayed by some of Darwin鈥檚 disciples is a measure of the scientific
credentials of Darwin鈥檚 ideas or of the man himself. In The Expression of
Emotions in Man and Animals it is clear that Darwin did not only wish to
argue that something might be so: he wanted to know whether it is so.

With the current hype surrounding Darwinian interpretations of human
behaviour, it is easily forgotten that Darwin was more than the chief proponent
of the idea of natural selection. He was also a prime advocate of the idea that
we are descended from apes. In 1872, 13 years after the publication of
Origin, Darwin argued in Expression that the evidence that we are
just another primate is, quite literally, staring us in the face. It is now
republished with a foreword, essays on the problem of universality and on
Darwin鈥檚 photographs, and Huxley鈥檚 obituary of Darwin.

As editor Paul Ekman makes clear in the foreword, Darwin was writing in a
particular philosophical context. The anatomist Charles Bell argued, from his
1806 Anatomy and Philosophy of Expression onward, that humans were
God-made separate creations and that our expressions bore evidence of this. We
have, he argued, many more expressions than animals, and unlike animals, we can
control them.

Darwin delivered a double riposte. He argued that very many of our
expressions are in anatomical, physiological and behavioural terms the same as
those of animals. And he described evidence that we cannot exercise will over
many of them. Ironically, some of the better evidence for this goes unmentioned.
With Expression, Darwin was one of the first scientists to publish a
book with photographs. He chose examples of both posed and natural subjects.
While the individuals artificially demonstrating certain expressions look like
embarrassingly awful ham actors, the pictures from life look genuine.

Darwin was not simply concerned with rebutting Bell. He was also interested
in the question of whether all races of humanity belonged to one species or, as
was then argued, were independently derived. This was why knowing whether human
expressions are universal or culturally dependent concerned Darwin. After
consulting his friends in the colonies about how the locals expressed their
feelings, he concluded that most expressions are universal.

In an excellent essay on universality, Ekman shows that Darwin was on the
right track, but that his flawed methodology meant that his contributions could
not be considered definitive. Darwin tested his ideas by using a very large
series of anecdotes, and this presents a number of difficulties. The anecdotal
evidence was not systematic, for example, so we have no idea whether he only
presented anecdotes consistent with his case. Darwin was aware of this
difficulty and discussed examples that he considered problematic.

Ekman also notes that the means by which the anecdotes were collected add
more potential biases. Writing to colonials to ask about native peoples may have
produced misleading findings, tainted by culturally specific ways of
interpreting facial expressions. Moreover, Darwin鈥檚 letters usually posed
questions that invited a given answer. Instead of asking which emotion was
expressed by the wrinkling of the eye and upwardly curved mouth, he would ask
whether happiness was expressed by these features.

With careful scientific testing, however, all such objections have since been
overcome. If for no other reason, Ekman鈥檚 essay is to be welcomed, as it
establishes that good systematic science can be done in this field, despite
obfuscatory attempts by certain social anthropologists. Darwin鈥檚 other
conclusion, that we are descended from apes, has similarly been put through
stringent scrutiny. From our knowledge of our genes and those of primates we now
have much better evidence of our ancestry than Darwin could have dreamt of.

You might reasonably ask why anyone should read this book, apart from its
obvious interest as an historical classic. Ekman鈥檚 essay on universality is a
good reason, as is Phillip Prodger鈥檚 very closely researched discussion of the
book鈥檚 photographs. Here we learn that they are not quite what they seem. They
are, in fact, photographs of detailed etchings, copied from the original
photographs! Between the original and the etching, details changed, often on
Darwin鈥檚 instructions.

The editor also provides very helpful commentaries in the text on the current
status of Darwin鈥檚 ideas. Ekman鈥檚 scholarship extends to updating and correcting
the text to be as near to what Darwin intended as possible. Much to the editor鈥檚
credit, the book is both scholarly and lively.

For me, however, the real wonder of Darwin鈥檚 books is the way they offer an
insight into the man. It seems clear that Bell鈥檚 argument must have bothered him
from very early on. I cannot see any other way of understanding how Darwin
related so many closely observed details of the expression of animals and of his
children accrued over such a time scale. Darwin鈥檚 ability as an observational
scientist is easily forgotten in an age when his name is synonymous with natural
selection.

More than this, it is wonderful to have a glimpse of Darwin鈥檚 critical
scientific instincts. Darwin realised that he had not only to 鈥渋nterpret鈥�
findings in the light of a theory, but also to look for circumstances in which
his theory predicted one thing, but an alternative was equally plausible. To
discover whether our expressions are innate or learnt, for example, he asked
whether people born blind show the same expressions as everyone else.

In these terms, then, Darwin is not dated. This is the same method of testing
hypotheses鈥攂y relying on the notion of falsifiability鈥攖hat is found
in everyday science the world over. Yet the same process can be used to show
that Darwin was wrong on many counts. For example, he theorises a great deal
about the role of acquired characteristics in the evolution of expressions. Such
Lamarckian inheritance makes predictions about the way information is
transmitted from one generation to the next. For the most part the predictions
are not borne out, and hence we can reject the ideas.

By equal measure, it is to the credit of Bell that we can consider his thesis
refuted. He laid out the facts that we would see if he were right and,
conversely, those that we would expect if he were wrong. His theory was thus
framed as falsifiable. The 46 per cent of Americans who, according to a 1991
Gallup Poll, still believe that some time in the past 10 000 years God created
us more or less in our present state, should take a leaf out of Bell鈥檚 book.
Even better, they should read Darwin.