Story highlights Though he didn't name Trump, Obama's target was apparent

The speech echoed similar shots he's taken at Trump

(CNN) President Barack Obama took aim Sunday at presumptive Republican presidential candidate Donald Trump while delivering the commencement address at Rutgers University, telling graduates to tout their knowledge, not brag about their ignorance.

Though he didn't name Trump, Obama's target was apparent.

"In politics and in life, ignorance is not a virtue," he told the more than 12,000 graduates in New Brunswick, New Jersey. "It's not cool to not know what you're talking about. That's not keeping it real or telling it like it is. That's not challenging political correctness. That's just not knowing what you're talking about. And yet we've become confused about this."

Obama's comments at Rutgers echo similar shots he's taken at Trump -- also without naming him -- during recent appearances.

The President also told the graduates to stand up to those who say that America was better in the past and dismissed the idea of building walls.

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