Stevie Wonder is using Martin Luther King Jr. Day as an opportunity to highlight the lack of progression around racial inequality in the U.S. 

The music icon took to Twitter to share a video in honour of the important occasion on Monday, Jan. 18.

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“Dear Dr. King, I met you when I was 14 years of age. You were a true hero and you became an inspiration,” Wonder recalled. “I’ve been blessed to write songs of hope, love and motivation, many of them inspired by your life. More than any award I’ve ever received, I want you to know that I am thankful for how you influenced my place of love, which allowed me to try to push the needle of love and equality forward.”

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Addressing America’s lack of advancement around inequality since King’s death, he continued, “For 36 years, we’ve had a national holiday honouring your birthday and principles, yet you would not believe the lack of progress. It makes me physically sick. I am sick of politicians trying to find an easy solution to a 400-year problem.”

The “Isn’t She Lovely” singer also called upon the Biden-Harris administration to “launch a formal investigation to establish the truth of inequality in this country.”

“It is time to formally seek the truth and formally declare facts,” he said. “We need a truth commission that forces this country to look at its lies.”

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Concluding his message, Wonder added, “Dr. King, these times require courage, as they did when you lived and paid the ultimate price. On this day, a day in your honour, I pledge to have the courage to say what I see and acknowledge what I hear.”