Here's a conversation on Twitter which occurred during former South African President Nelson Mandela's memorial service in Soweto.
President Robert Mugabe of Zimbabwe got very loud cheers from people in the stadium when he arrived for the memorial at Johannesburg's FNB stadium on Tuesday.
Someone tweeted: "If I was a white African I would ponder a lot on the enthusiastic welcome given to Mugabe. Oh shit. I am."
Response to tweet: "I thought you was a South African. African equates to 'black' #justsaying".
Then this reply, from someone else: "Dialogue between the black+white African is key & yet we shy away 4rm [sic] it! We haven't talked since #madiba made us in court rooms."
The sometimes uncomfortable issues about land reforms and indigenisation are still simmering, just below the surface, clearly. Some African countries, like South Africa, choose not to talk this openly about the issue, while others are more than willing to do so, even showing off about it. (Mugabe's Zimbabwe is very much in the latter camp.)
So what makes one indigenous to Africa? Is it the colour of one's skin or that one was born on the continent?
Are white-skinned people who are born in Africa Africans? If they are not, then what are they?
Nelson Mandela encouraged the different races to forgive and move on as Africans. But we know there is still a long way to go before his dream is fully realised. The simple truth is that, even today, some blacks don't like whites and some whites don't like blacks.
Those comments on Twitter suggest we need to feel comfortable enough to talk about this. What makes us Africans?
But are blacks and whites ready to do that?