There's a poignant story early in the Nidda tractate we're working our way through these days. Rabbi Eliezer had a big disagreement with some of his peers about an arcane matter of ritual purity. Rabbi Yehoshua forced through his position and it was generally adopted. After the death of Rabbi Eliezer, however, Rabbi Yehoshua changed the ruling to the position of Eliezer. So far, the Mishna. The Gemara, maybe 200 years later or more, picks up the story and asks for an explanation. The one given is that R. Eliezer was too close to the Sadducies ("Shmuti" is the term used), and R. Yehoshua felt that giving him any ground would give credibility to his other positions and that couldn't be allowed. Once he was dead there was no danger, so his positions where correct could now be acknowledged.
Later in the tractate there's another discussion about sources of authority for knowledge and determining Halacha. The duscussion turns on a factual question about how far a feotus develops in its first 40 days. Rabbi Yishmael outlines his position, at which point someone (unnamed) tells him of a case where Cleopatra queen of Alexandria (that's how she's described) carried out an experiment on two of her slaves whom she had sentenced to death. She had them both inseminated, and then executed on the 41st day; on opening their wombs it was fond that both the male and female feotus had recognizable form. R. Yishmael responded sharply: I'm proving my point with a passage from the Bible,and you're bringing proof from the fools?!?
That's a pretty clear position, you'd think: that scholastic investigation trumps empiric investigation. It's also what you'd expect from large swathes of pre-modern scientific investigation. Except that the Gemara then offers a series of possible empiric explanations for Cleopatra's findings: perhaps one of the women was pregnant before she was convicted and inseminated? Or perhaps the guard had a bit of fun of his own, and the true insemination wasn't 41 days before the execution but less? The subtext being that empiric experimentation can be convincing - if your methodology is watertight. A very modern idea, that.
This thread is introduced and explained here. And then here's an item from Tablet Magazine which explains why I don't blog anymore.