Why do we say “write any quote and sign by Mark Twain’s name and no one would object”?

Question

Once I was writing a “Preface” for my friend’s college assignment book, I wanted to make it attractive so I thought of some quote related to prefaces of books. I consulted on an online forum and someone there said

Write anything you like, mark it Mark Twain’s name and no one would object.

You may say it was just his opinion but it’s not entirely true. People do have understanding that a quote by Mark Twain can’t be analyzed for its source. Why is that? Is it because Twain wrote about a large number of topics? Or is it because he was humorous and people have tendency to accept him easily?

Answer 1

I think this is referring to the fact that many of the famous quotes attributed to Mark Twain weren't actually his. (He did come up with a remarkable number of funny sayings.) So write anything you like, accredit it to Mark Twain, and people will believe he said it. Below are just a few of many quotes that are falsely attributed to him.

Mark Twain did not originate the quote

There are three kinds of lies: lies, damned lies, and statistics.

Nor did he say

The coldest winter I ever spent was a summer in San Francisco.

Nor did he say

If voting made any difference, they wouldn't let us do it.

Nor did he say

Never put off until tomorrow what you can do the day after tomorrow.

Answer 2

People do have understanding that a quote by Mark Twain can’t be analyzed for its source

I don't think that's the issue. I have never heard that particular witticism, but I found myself nodding in agreement — Mark Twain is such a towering giant in American literature that it is easy to imagine how people would find no need to think about anything attributed to him (because how could it be wrong, if it was said by such an esteemed figure as Mark Twain). Although I would say that this is a bit tongue-in-cheek, and meant to poke fun at some slightly snobbish members of the educated middle class, who would pretend to know any made-up quote as long as it's attributed to Mark Twain.