The highly praised film Skin - which recalls the sad fate that befell that Laing family in the 1960s - offers South Africans a timely reminder of the cruelties of apartheid in general and of the iniquitous doctrine of racial classification in particular.

Sandra Laing was born to a conservative, apartheid and National Party supporting family in Piet Retief near South Africa's border with Swaziland. Instead of enjoying life as a young girl, she suffered the torments of rejection. Instead of bringing joy to her parents, she brought them anguish and shame through no fault of her own.

Unlike her parents, Sandra was dark-skinned and her hair crinkly instead of straight or wavy, probably because one or both of her parents had inherited Negroid as well as Caucasoid genes from one of their forebears. Sandra was mocked and ostracised at the local white school and, according to one account, eventually escorted out of the school by two policemen as if she was a common criminal.

Given her rejection by white children of her age, most of her childhood friends were black and later, when she was 15, she fled to Swaziland with a young black man. Had she lived in a British colony in an earlier age, she would have been said to "have gone native."

At the time of Sandra's birth in 1955, the ruling National Party was pressing ahead with its drive to classify all South African into one of four major racial categories: white, coloured, Asian and black. Race classification was hierarchical, with the opportunities accorded to white being substantially greater those which filtered down to blacks. Coloured and Indian occupied an intermediate position.

Infused with the ideological of apartheid, the National Party government of D F Malan sought to hermetically seal the designated races off from one another. It was an absurd as well as a cruel project. Viewed in context of the Immorality Act, which criminalised inter-racial sexual intercourse and international marriages, it is reminiscent of the Nuremberg laws of Nazi Germany.

The scholarly Wilmot James, who represented the Democratic Alliance in parliament, reckons that at least 10 % of those who were classified as white in the 1950s were white-looking coloureds who had moved into white areas and made friends with whites ahead of the implementation of the Population Registration Act.

On the same note it should be recorded that studies undertaken in the 1970s, summaries of which were published in the press, calculated that between 6 and 7 % of the gene pool of white South Africans was derived from their black and brown compatriots, though, of course, they were not evenly distributed in the white community as a whole.

The unequal distribution of these "alien" genes accounts for the snide remarks of white who thought themselves to be racially pure about their darker skinned racial kinsfolk having "a |touch of the tar brush."

But if it is salutary for whites in South Africa today to contemplate the evils of racial classification and the use of it to restrict the life chances of those consigned to the lower ranks of the racial hierarchy, the leadership of the ruling African National Congress should take cognisance of their own role in perpetuating a form of race classification.

President Jacob Zuma, like President Thabo Mbeki before him, is a strenuous proponent of "transformation," a vaguely defined policy objective which most South Africans understand and support as a constructive policy aimed at reconstructing South Africa as a free, open and non-racial society.

Unfortunately, however, it involves racial preferencing in favour of blacks through the policies of affirmative action and black empowerment as a means of redressing past discrimination against and oppression of black South Africans by previous white governments.

The difficulty is compounded by the steadfast refusal of the Mbeki and Zuma administrations either to set a deadline to its racial preferencing policy or, at the least, to exempt young whites who were grade one or two pupils when Nelson Mandela was released from prison in February of 1990 and who should not be held accountable for past injustices.

Racial preferencing policies self-evidently require racial classification in order to identify those who qualify for preferential treatment and those who do not. Thus post apartheid South Africa is characterised by a glaring anomaly: an ANC government that proudly proclaims its commitment to non-racialism while retaining a form of race classification and "positive" or "fair" discrimination in favour of blacks.

There is another even graver problem: the ANC's steadfast commitment to the doctrine of proportionality or represenitivity which seeks to ensure that the racial profile of government departments and private companies reflect the racial profile of the population as a whole.

Apart from leading to employment of people on the basis of skin colour rather than experience or qualifications, at the risk of administrative incompetence and, in extreme cases, even administrative collapse, there is an even graver objection.

Representivity or proportionality has an unfortunate history: it was used by the Nazis in German in the early years of Adolf Hitler's Third Reich to restrict the number of Jews in the legal, medical and teaching profession to the proportion they constituted of the German populations as a whole.

It is significant, too, that Hendrik Verwoerd, who was later to acquire notoriety as the "high priest of apartheid," advocated it use in South Africa in the 1930s to limit the number of Jews in he profession to their proportion of the population. His aim in doing so was to ensure that Afrikaners and their English-speaking compatriots were similarly representative in proportion to the numbers in the white population as a whole.

Black people were apparently not considered at all by Verwoerd in the 1930s, possibly because the number of black professional people was minute in those years. Later, when he became Prime Minister, he deployed a different rationale to restrict the number of black people, arguing that they should exercise their skills in their own areas and not in white-designated South Africa.

Whatever its theoretical justifications in South Africa, the doctrine of proportionality is a potentially pernicious doctrine open to abuse as a weapon to be wielded against minorities or selected minorities by the dominant majority.

Democracies are not merely characterised by majority rule and the holding of regular elections under clear and equitable rule. The defence of minority rights is an important and perhaps even indispensable distinguishing feature of democracy.

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