Warren Buffett says this one investment "supersedes all others"

Billionaire investor Warren Buffett says the very best investment you can make is one that "you can't beat," can't be taxed and not even inflation can take away from you. "Ultimately, there's one investment that supersedes all others: Invest in yourself...
https://www.cnbc.com/2017/10/04/warren-buffett-says-this-one-investment-supersedes-all-others.html