Who has been normally credited with saying: "When in doubt tell the truth"?

Mark Twain is normally credited with saying: "When in doubt tell the truth". He thought that this meant one confounded enemies and astounded friends. The quote points out that, in order to be a good liar, or tell a very good lie, one has got to remember what is said exactly. By telling the truth, a person doesn't have to have a good memory.

Mark Twain is said to have said, “If you tell the truth you don’t have to remember anything,” meaning if you tell a lie you have to remember what lie you told and who received it. This truism can also be expressed as, “it takes more effort to lie than it does to tell the truth.”

It may now be doubtful in some circles that Mark Twain said this exact phrase. If he did, the documentation has been lost. The basic gist of the quote is true, and modern science proves it.

Samuel Langhorne Clemens (aka Mark Twain,1835 – 1910) was born in Florida, Missouri and died at age 74 in Stormfield House, Redding, Connecticut. He was an experienced, industrious, ambitious American writer, humorist, entrepreneur, publisher, and lecturer. He has been lauded as the "greatest humorist the United States has ever produced", and William Faulkner, the famous American-baroque writer like to call him "the father of American literature".