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Pamphlet 1 - Lice and Mice

Sages and Mistakes

The Gemara in Shabbat 107b rules that one is permitted to kill a louse
on Shabbat because it does not sexually reproduce. This statement
should be very troubling to the thinking student because, while the
entire ancient world believed that animals could be created through
spontaneous generation, we have known since the 17th century that this
is incorrect. Animals that had been thought to be spontaneously
generated were observed reproducing. With the aid of magnifying tools,
lice eggs were found! How can an halacha be based on an observably
incorrect fact? What does this do to our faith in the sages and the
integrity of halacha?

These are all valid questions but we would be foolish to think that
they had never been asked before. The great rabbis of the past few
centuries were very much aware of this issue and we need to search for
their treatments of this topic. For a longer analysis of this and
similar issues, see our essay on Torah and Scientific Developments.

But first we must ask a basic question. Can the holy sages make
mistakes? Granted, they poured all of their physical and mental
energies into preserving and safeguarding the Jewish faith. But is it
possible that with all this effort, with all the critical reviews and
arguments by other rabbis anxious to remove all logical flaws, is it
possible for an halachic ruling that was universally accepted to be
mistaken?

...

- quoted from Aishdas at
http://www.aishdas.org/toratemet/en_pamphlet1.html

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