The Talmud is a collection of discussions among Rabbis about the exact meaning of some of the laws in the Torah. For example, the section "Sabbath" goes into great detail about just what is to be considered "work" which is forbidden on the Sabbath. At one place the discussion gets into the area of avoiding temptation to engage in work on the Sabbath.

A woman should not look in a mirror on the Sabbath. Why? Because she might see a grey hair, and be tempted to pull it out. This is the same as cutting a hair off, and cutting hair is clearly working on the Sabbath.

There are many other laws. For example, making a fire on the sabbath is forbidden. But just what counts as "making a fire" ? How about making a spark, which could cause a fire? And since turning on a light switch makes a (very small) spark, really Orthodox Jews today don't touch light switches. Except that the rich enough, after consulting experts in solid-state physics, have installed in their houses circuitry which lets them turn on lights by simply moving near enough to a plate on the wall, and the circuitry doesn't involve making sparks.

Isn't science wonderful?

Ken Smith