When did Mark Twain say Honesty The best of all the lost art?

Mark Twain never actually said "Honesty is the best of all the lost arts." This phrase is a misattribution and there is no evidence that he ever uttered those words.

While Twain was known for his wit and wisdom, this particular quote is likely a modern fabrication. It's a great sentiment, but it doesn't seem to be traceable back to him.