What was the court's dissenting opinion in Plessy v. Ferguson?

In Plessy v. Ferguson the Supreme Court held that the state of Louisiana did not violate the Fourteenth Amendment by establishing and enforcing a policy of racial segregation in its railway system. Justice John Marshall Harlan wrote a memorable dissent to that decision, parts of which are quoted today by both sides of the affirmative action controversy. One statement often quoted by opponents of race-conscious affirmative action programs is Harlan's assertion that the Constitution is "color-blind," which can be found in the excerpts below.