It’s easier to fool people than to convince them that they have been fooled.

Mark Twain (1835-1910) American writer [pseud. of Samuel Clemens]

(Spurious)

Not found in Twain's writings. The earliest attribution to him appears to be in 2011. The connection to Twain may be his (authentic) comment, "How easy it is to make people believe a lie, and how hard it is to undo that work again!"

For more discussion of this quotation, see Quote Origin: It’s Easier To Fool People Than To Convince Them That They’ve Been Fooled – Quote Investigator®.