This was the testimony of a clinical psychologist in the trial of the so-called Skierlik killer.
Nel had never been in a position to be exposed to other cultures, Kobus Truter testified.
One of the reasons was because his parents, Hennie and Corrie Nel, had taken him out of mainstream school in order to home-school him.
"The idea of a rainbow nation did not exist there (in the Nels' home) or in Swartruggens," Truter said.
Sentencing
Nel, 19, will know his fate on Friday.
While advocate Sello Maema, for the State, on Wednesday asked for life imprisonment in the Mmabatho High Court, advocate Johan Engelbrecht SC, for Nel, asked for a sentence of only 30 years.
During arguments Judge Ronald Hendricks told Engelbrecht that, because Nel had pleaded guilty to racially motivated crimes, the community had to get a clear message that this kind of thing could not be tolerated.
Earlier this week Nel pleaded guilty to four counts of murder, 11 of attempted murder and one each for the illegal possession of a firearm and ammunition.
Maema said the Skierlik community in the informal settlement outside Swartruggens wanted to know from Nel why he shot people there on January 14 this year.
Nel killed four people - Enoch Matshelanoka, 10, Elizabeth Moiphiltlhi (two months) and her mother, Annah, and Sivuyile Peye - and injured several others.
"These people were defenceless," Maema said.
"Some of them were relaxing under a tree, others were gardening or just walking down the street.
'Sick boy'
"What makes it worse is that they were people of colour. Why did this happen?"
Engelbrecht said: "We are dealing with a 'sick' boy here - sick in the sense that he shows signs of post-traumatic stress syndrome, anxiety and every possible form of destructive disorder."
Truter said Nel had never consciously planned to kill the residents of the Skierlik informal settlement as such. It could have been anyone.
Nel had told him earlier that he had considered going to a nearby caravan park, which is mostly inhabited by whites, to randomly start shooting people.
Another possibility was to stand at a traffic intersection and mow down everybody, regardless of their colour.
"He (Nel) was angry with the world for what everyone and everything had done to him," Truter testified.
"He had formed the intent to kill."
Psychologist's report
Here is an exercise from a report by clinical psychologist Kobus Truter in which Nel was asked to complete the sentence
I like shooting and hunting;
The happiest time can't think of a happy time;
I feel upset and stressed;
At night in my bed I can?t sleep;
I would like to know how my life got to be so ****;
If I can one day afford it I would like to get as far away from this country as possible;
I regret most of my life;
I suffer from too much stress;
My nerves are shot;
My biggest worry is that I don't have much of a life left;
I have made a firm decision to get as far away from people as I can;
I am sorry about too many things to write down.
