In the 16th century, an anecdote about the monks’ discussion of the number of teeth in a horse was popular. The discussion was supposed to take place two centuries earlier.
And so a group of monks argued about how many teeth the horse had. The discussion lasted several days and three factions were separated. From Aristotle through the „ancient texts”, the number of teeth was 30, 45, or 50. After several days of fierce discussion, the young monk suggested to go outside and check how many teeth the horse actually has.
The proposal to revise the assumptions sparked outrage among the elders. They beat the young monk and threw him out the door. After several days of theological debate, they came to the same conclusion.
I could add a few paragraphs about validating assumptions and using data. But why. This story requires no comment. Don’t be an old monk.