MSNBC's erratic Hardball host, Chris Matthews, has again gone off the deep end with his nonsense talk about the Constitution's three-fifths clause. He's claiming that conservatives believe black people are, or once were, only three-fifths of a person.

Why does a group of people that always loses elections or tends to do lately, why do they call themselves American people because - do they still count blacks as three-fifths? Three-fifths of a vote?

He's so off-base on this one it's almost laughable. It's actually cryable. The Three-fifths Compromise of the Constitution was simply a mathematical formula the Founders employed to limit the power of the slaveholding states. By refusing to give them full credit for the people in their states who were "held to service," anti-slavery delegates to the Constitutional Convention were placing Southern states at a disadvantage. They could not claim the full number of people in their states for representation in Congress or for clout in the Electoral College.

James Madison attended virtually every session of the Constitutional Convention. He reported that Connecticut's Roger Sherman objected strongly to laying an import duty on slaves brought to the U.S. from West Africa.

Other anti-slavery delegates tried to persuade "Mr. Sharmin," as Madison pronounced the Connecticut Yankee's name, saying that this was a way of discouraging the importation of slaves. Sherman was unyielding. He was not willing even to hint in the text of the Constitution, Madison tells us, that "there could be property in man."

Abolition champion Frederick Douglass studied Three-fifths question with great diligence. He concluded that the Three-fifths Compromise was an anti-slavery measure. Here's what the hero of his people had to say:

It is a downright disability laid upon the slaveholding States; one which deprives those States of two-fifths of their natural basis of representation....taking it at is worst, it still leans to freedom, not slavery; for, be it remembered that the Constitution nowhere forbids a coloured man to vote.

Here are some other facts to consider. At the time of the framing and ratification of the Constitution, several states were moving to emancipate their slaves. Seven of the original thirteen states abolished slavery. There was real hope that all would do so.

Can Chris Matthews deny that when a state emancipated its slaves, it got an electoral bonus? As soon as the slaves were freed, that state was allowed to count them for full representation in the House of Representatives and, of course, in the Electoral College.

It is clearly a tragedy of American history that not all the slave states followed the examples of Massachusetts, New York, and Pennsylvania, but the example was there.

Chris Matthews is not the only liberal jarringly wrong on the Three-fifths Compromise. Jesse Jackson and Al Gore ranted to campaign rallies in Pennsylvania in 2000 that George W. Bush's partisans thought black folks were only three-fifths of a person.

That was untrue, and they should have known better.

The New York Times editors continued this mangling of history with its bitter complaints about the Republicans' reading the Constitution when they resumed control of the U.S. House of Representatives in 2011.

All of this is part of the liberal attempt to deny historical truth. The truth is that the Democratic Party, with its base in the Old South, was the main impediment to Emancipation and Civil Rights for a full century.

Every vote cast against the Thirteenth, Fourteenth, and Fifteenth Amendments was cast by a Democrat.

Every vote cast against the Civil Rights Acts of the Reconstruction Era was cast by a Democrat.

Every vote cast in the U.S. Senate for thirty years to prevent anti-lynch laws was cast by a Democrat.

No one denies the leading role played by Hubert Humphrey and other white liberals in the final passage of the great Civil Rights Act of 1964 and the crucial Voting Rights Act of 1965. Nor should any Republican deny the errors of admitting the notorious segregationist Strom Thurmond to the Republican Senate Caucus in 1964 or of Republican Sen. Barry Goldwater voting against the Civil Rights Act.

But these errors were of limited duration. Weighed against a century and a half of Democratic Party obstruction of civil rights, simple justice should say the Republicans deserve their due.

Maybe we should give Chris Matthews movie money. Let's send Chris to see the movie, Lincoln. This Hollywood production doesn't get it all right, but it clearly shows that Lincoln and his fellow Emancipators were [Shhh! Don't wake the New York Times] Republicans!