If the entire scientific community and you come to opposite conclusions, that's not proof that you're right

A little bit ago Greta Christina wrote a post discussing what she called the Galileo Fallacy:

There's a form of very bad thinking that I see a lot in some very smart, thoughtful people.

The thinking goes like this:

"Great thinkers throughout history have had unpopular ideas that everyone disagreed with.

"I have an unpopular idea that everyone disagrees with.

"Therefore, I must be a great thinker."

I call it the Galileo Fallacy, in honor of something my old roommate Adele used to say: "The fact that everyone disagrees with you does not make you Galileo."

This "argument" is very common among cranks, people who believe: homeopathy; reiki; the moon landing was faked; 9/11 conspiracies; HIV doesn't cause AIDS; etc. I felt that Ms. Christina's post would be better served if a concrete example was offered:

This subject is attended by the same difficulty which has impeded the advancement of other departments of Natural History, as well as the Sciences of Astronomy and Geology. In their infancy, discoveries in these sciences, were regarded as inconsistent with the Mosaic account of the creation, and they have encountered determined opposition from well meaning and other religious persons. The scientific men who have been bold enough to speak truth, and to uphold the works of God, have been persecuted by those who mistake their own intellects for a measure of wisdom, and their own passions and prejudices for the will of heaven.

When Gallileo [sic] promulgated the great truth that the sun stands still, and the earth moves round it, he was attacked and persecuted by the whole priesthood--he was twice brought before the Inquisition and forced to renounce his doctrines.--Time, however, has served to show that Gallileo was right, and the Bible still stands "the rock of ages."

What was "this subject" that could be so favorably compared to Galileo's theory of heliocentrism, under attack as it was by an overwhelming conspiratorial organization dedicated to oppressing new ideas? The idea that blacks and whites weren't the same species. The quote was taken from Josiah Nott's "Two Lectures on the Natural History of the Caucasian and Negro Races". Some of Nott's ideas that he thought made him the 1844-era Galileo:

1st. That the mulattoes are intermediate in intelligence between the blacks and whites.

2d. That they are less capable of undergoing fatigue and hardships, than the blacks or whites.

3d. That the mulatto women are particularly delicate, and subject to a variety of chronic diseases.

4th. That the women are bad breeders and bad nursers--many do not conceive--most are subject to abortions, and a large portion of the children die young in the southern States.

5th. That the two sexes when they intermarry, are less prolific than when crossed on one of the parent stocks.

6th. That Negroes and mulattoes are exempt in a surprising degree from yellow fever.

Yeah. Time isn't going to prove that you were a brave martyr fighting for truth against the dogmatic establishment if you're simply wrong.