Uncontrollable reddening of the cheeks, and sometimes the ears and neck, is associated with embarrassment and guilt.
Charles Darwin made the most interesting suggestion: that blushing is a warning that the individual who is blushing is not to be trusted, as he or she has violated the mores of the group or has committed some crime. This notion that blushing is a visible warning sign that an individual is not to be trusted Darwin puts forward in
Expression of the Emotions in Man and Animals (1872). Part of his evidence is that children before the age of understanding social rules do not blush, for 'the mental powers of infants are not yet sufficiently developed to allow of their blushing. Hence, also, it is that idiots rarely blush.' Blushing (and also weeping and sobbing) is found only in man and not in other primates, who are generally supposed (in spite of some recent contrary evidence) not to have cognitive understanding of social mores or their violation. This is not to say that only humans have social mores, only that we alone appreciate and evaluate them, and act on our assessments of social situations, and monitor our successes and failures and the appropriateness of our behaviour in situations that had no precedence earlier in evolution. It seems that only humans have the understanding to be embarrassed — and so to blush.
For Darwin 'blushing is the most peculiar and the most human of all expressions'. He goes on to suggest a psychosomatic origin: 'we cannot cause a blush by any physical means. ... It is the mind which must be affected.' But this is not the
conscious mind, for (writing nearly twenty years before
Sigmund Freud was born) Darwin points out that blushing is not under control and that, further: 'Blushing is not only involuntary; but the wish to restrain it, by leading to self-attention, actually increases the tendency.' That it is an innate sign of mental states is confirmed by blushing in blind people.
Women blush more than men. Darwin wished to discover how far down the body blushes extend, so he adopted the ingenious notion of asking his medical friends 'who necessarily had frequent opportunities for observation'. His friend Sir James Paget (1814–99, who wrote the standard texts,
Lectures on Surgical Pathology and
Clinical Lectures) reported that: 'with women who blush intensely on the face, ears, nape of the neck, the blush does not commonly extend any lower down the body'. He never saw an instance in which it extended below the upper part of the chest. Darwin considers whether it is the exposure of the face to temperature changes that makes the capillaries specially labile; but decides, rather, that the face is intimately associated with the brain and that the blushing is primarily facial, at least in English women, because of the 'attention of the mind having been directed more frequently and earnestly to the face than any other part of the body'.
What we would now call the psychosomatic basis of blushing was pondered in astonishing depth by Darwin, as he considered that its mental effects may be
reversible. He refers to the observation that when patients are given nitrite of amyl they blush in the same restricted regions as with embarrassment. 'The patients are at first pleasantly stimulated but, as the flushing increases, they become confused and bewildered. One woman to whom the vapour had been administered asserted that, as soon as she grew hot, she grew
muddled.' Although all this was said well over a century ago there is little to add now, apart from its detailed physiology, to Darwin's comments on blushing.
(Published 1987)— Richard L. Gregory
