One was the tendency to stereotype people in terms of their race and ethnicity by making sweeping generalisations.
We were quick to pass judgment on an entire community based on the behaviour of one or two people.
For instance, because people like Penny Sparrow and Vicki Momberg said racist things in public, many assumed all whites are bigots.
A crooked Indian businessman gets caught with his fingers in the cookie jar and an entire community acquires an unfair reputation.
Three black youngsters are prime suspects in a horrific murder and robbery case in a posh suburb and people shut their doors at the sight of any black man approaching.
Which brings me to the real-life and tragic story of Mollie Tibbetts, a bubbly 20-year-old student in Iowa in the US, who disappeared on July 18 while jogging near her home.
After a month-long search, her body was found and police arrested Cristhian Bahena Rivera.
It was a murder that shocked the nation, but just as tragic was the reaction to news that Rivera turns out to be an undocumented immigrant from Mexico.
In minutes, US President Donald Trump and other Republican politicians pounced on Mollie Tibbetts’s killing, politicising the tragedy by demanding a wall be built to keep out the “illegal aliens”, and implicitly blaming Democrats (who support open borders) for Tibbetts’s death.
A deeply grieving Tibbetts sr would have been forgiven for ignoring this blatant politicisation of his daughter’s killing but his reaction is a lesson for all South Africans.
He told Americans his stepdaughter “whom Mollie loved so dearly” also happens to be of Latino origin. So too are Mollie’s nephews and his grandchildren.
“That means I am Hispanic. I am African. I am Asian. I am European. My blood runs from every corner of the Earth because I am American.
“As an American, I have one tenet: to respect every citizen of the world and actively engage in the ongoing pursuit to form a more perfect union.”
In his mind, to knowingly foment discord among races is a disgrace to the American flag.
“It incites fear in innocent communities and lends legitimacy to the darkest, most hate-filled corners of the American soul. It is the opposite of leadership. It is the opposite of humanity. It is heartless. It is despicable. It is shameful.”
His plea to the American people was: “Let’s turn towards each other with all the compassion we gave Mollie. Let’s listen, not shout. Let’s build bridges, not walls. Let’s celebrate our diversity rather than argue over our differences. I can tell you, when you’ve lost your best friend, differences are petty and meaningless.”
We salute you, Mr Tibbetts!