He was, to be fair, an interesting taxi-driver. He belonged to the Zion Christian Church, which has made a virtue of shunning political engagement. In those days, F W de Klerk entertained the hope that the two million-strong ZCC would provide his National Party with a window into the black vote.
The professor asked the driver: 'Will you vote for the National Party?'
'Will you vote for Inkatha?'
'Will you vote for the ANC?'
'So, who will you vote for?'
'I will vote for Mandela.'
I've quoted that little exchange often in response to people who have asked me whether the ANC would really clean up the black vote when the time came. The ANC in itself without Nelson Mandela is a mightily potent force. The initials echo with historical resonance. But, heavily politicised as many blacks inevitably are, there are many who have never attended a political rally, who are not consumed by the great questions of the day, who concentrate their energies on getting by from day to day.
Evidently the ZCC taxi-driver lived up to his word. Everything indicates that the overwhelming majority of the black population has voted for Mandela.
Yesterday afternoon I went out to the main counting-station for the greater Johannesburg area and learnt unofficially, from international observers, that the ANC had picked up more than 90 per cent in Soweto, South Africa's biggest township, and similar proportions in smaller townships on the periphery like Duduza and KwaThema.
Were it not for the Mandela factor the ANC might have scored 10, maybe 20, per cent fewer votes and Mr de Klerk's dream that blacks would forgive and forget the past, might have yielded something of substance at the polls. The Pan-Africanist Congress, which peaked politically in the early Sixties, might have gained from black people dredging up the memory of the past.
But Mr Mandela, at 75, is the present. He is the living legend - and there is no more important factor in an election - the best- known name in South Africa. Independent of his merits, the fact is that black people revere him.
Mr de Klerk, against that, had no chance. Likewise the PAC, which, it is now clear, will struggle to garner 2 per cent. A lot of white pollsters, perhaps giving vent to the fears generated by the PAC's 'one settler, one bullet' slogan, had predicted they would do better. Eminent academics had predicted 10 per cent. But that was a function, partly, of not spending enough time in the townships. I've travelled to more than I can remember and have found it unusual to come across a PAC supporter, much less a functioning PAC office.
There are three principal reasons for the PAC's failure to attract support for their version of the liberation struggle. First, their leader, Clarence Makwetu, has the charisma of an ox. Second, they are abysmally lacking in funds and organisation. Third has been the readiness with which their tiny armed wing has claimed responsibility for the handful of racist attacks on whites in the past two years, notably the massacre at St James' Church in Cape Town, which is further confirmation of the distaste with which most black South Africans view those who try to make political capital out of racial antagonism.