From Sex, Gender and Society (1972)
Everybody knows that men and women are different. But behind this knowledge lies a certain uneasiness: how different are they? What is the extent of the difference? What significance does it have for the way male and female behave and are treated in society? While the first questions are factual ones, the last is a question of value. In practice, of course, fact and value are not always separated, and the confusion between them has been crucial in the debate about sex differences. This debate has been carried on much more keenly during some historical periods than others. It seems to be revived at times when the existing roles and statuses of male and female are changing...
The enduring questions are these: does the source of the many differences between the sexes lie in biology or culture? If biology determines male and female roles, how does it determine them? How much influence does culture have? These questions are more meaningful now than they were in the previous debates about sex differences, for the simple reason that we are now able to disregard (if we wish) almost all the so-called consequences of the reproductive division between the sexes. Fertility control and the safe artificial feeding of infants enable couples to choose when they shall have babies, and who shall feed them. The former is an achievement of personal relevance for all women, while the latter is of potential (though usually underrated) relevance to both sexes, since it makes it possible to distribute both the work and the joy of childrearing between people regardless of their biological sex: that is, it could bring men back into the home.
But, however much we could change the traditional involvement of women with their biological roles, the direction of change remains a question of choice and of value. It is not enough to point out that the traditionally incontrovertible argument for the sex-differentiated society has had its foundations removed with the advance of pills, loops, rubber devices, synthetic human milk and sterilised feeding bottles. Arguments long believed in have an alarming tendency to remain suspended in thin air by the slender string of passionate, often irrational, conviction. They seem not to need their foundations to survive. Technology has altered the necessary impact of biology on society, but our conceptions of masculinity and femininity have shown no corresponding tendency to change. The lag between the two points to a crucial distinction it is necessary to make in our thinking about male and female roles - the distinction between 'sex' and 'gender'. 'Sex' is a word that refers to the biological differences between male and female: the visible difference in genitalia, the related difference in procreative function. 'Gender' however is a matter of culture: it refers to the social classification into 'masculine' and 'feminine'. The distinction between 'male' and 'female' on the one hand, and 'masculine' and 'feminine' on the other, makes it possible to clarify much of the argument about sex differences...
As John Stuart Mill observed in 1869, the topic of sex differences is one on which almost everybody feels qualified to dogmatise, while 'almost all neglect and make light of the only means by which any partial insight can be obtained into it.' What Mill meant was that people rarely refer to the evidence about the differences and similarities between male and female before pronouncing their conclusions. While deploring this tendency, he admitted that sound evidence on the subject was sadly lacking in his time: we need, he said, to study 'the laws of the influence of circumstances on character.'
The rise of the social sciences has, since Mill wrote, provided us with exactly this kind of evidence...The task is to disentangle 'sex' from ‘gender' in the many fields where the existence of natural differences between male and female has been proposed, aiming to replace dogmatism by insight, and attempting to separate value-judgments from statements of fact.