Obama made a rare public appearance to deliver a biting critique of Trump's worldview - without saying his name

Siphiwe Sibeko/Reuters

President Obama delivered a speech in honor of Nelson Mandela's 100th birthday in South Africa on Monday.

• Former President Barack Obama offered a sharp rebuke of his successor's worldview.
• He delivered the 2018 Nelson Mandela Annual Lecture in South Africa, slamming "strong man" politics and the rejection of intellectualism he feels is permeating today's political culture.
• Obama did not once say President Donald Trump's name during the address, but his words represented a biting critique of the current president's political philosophy. 
• Obama concluded his speech by encouraging young people to stay politically active and to have faith in democracy despite how "slow" and "frustrating" it can be at times. 

Former President Barack Obama on Monday offered a sharp rebuke of his successor's worldview as he delivered the 2018 Nelson Mandela Annual Lecture in South Africa, slamming "strong man" politics and the rejection of intellectualism he feels is permeating today's political culture. 

Obama did not once say President Donald Trump's name during the address, which coincided with what would've been Mandela's 100th birthday. But his target was clear as he offered a biting critique of the current president's political philosophy. 

The former president used the speech as an opportunity to outline what he views as troubling trends in the political arena at present. 

"Strong man politics are ascendant suddenly," Obama said. "Whereby elections and some pretense of democracy are maintained the form of it. But those in power seek to undermine every institution or norm that gives democracy meaning."

'The free press is under attack'

As Trump once again took to Twitter on Monday to denounce "fake news," a phrase he employs in response to negative coverage of his actions or rhetoric, Obama noted how "the free press is under attack."

In this context, Obama urged people to reject xenophobia and "rabid nationalism," warning that history shows countries that embrace "doctrines of religious or racial superiority" eventually find themselves "consumed by civil or external war."

"You can be proud of your heritage without putting someone else's heritage down," Obama added. 

Obama's speech came after Trump's high-profile visit to Europe, during which he claimed the bloc was "losing its culture" because of immigration. 

"These people who are so intent on putting people down and puffing themselves up are small-hearted. There's something they're just afraid of," Obama said.

'You have to believe in facts'

In addition to warning against the dangers of excessive nationalism, the former president expressed concern over the apparent rejection of objective truth among leaders at present. 

"You have to believe in facts. Without facts, there's no basis for cooperation," Obama said. "Unfortunately, too much of politics today seems to reject the very concept of objective truth. People just make stuff up."

An analysis from The Washington Post shows Trump has made at least 3,001 false or misleading claims so far as president. 

Obama concluded his speech by encouraging young people to stay politically active and to have faith in democracy despite how "slow" and "frustrating" it can be at times. 

"Keep believing. Keep marching. Keep building. Keep raising your voice. Every generation has the opportunity to remake the world," Obama said. "Mandela said young people are capable when aroused of bringing down the towers of oppression and raising the banners of freedom. Now is a good time to be aroused."