Eiruvin 75a, b

Daf 75a is a long conversation about a metaphor: how "the prohibited foot of a person" might define a courtyard as prohibited or permitted.  Of interest are the different rules that apply to inner and outer courtyards.  The very start of this daf continues yesterday's conversation and focuses on the prohibition of Jews living together with a Gentile.  I would like to understand  the reasoning behind this rule, both based on "reason", as the rabbis would say, and based on other unspoken sociological factors (anti-semitism, 'real' dangers, perceived anti-semitism, tribalism, anti-Gentile/anti-stranger stereotypes, etc.).

Daf 75b examines both the inner and outer courtyards, the number of Jews/Gentiles living in those courtyards, and the renunciation of rights.  Numerous possible combinations of these factors are put together to determine when and where carrying is allowed on Shabbat.  At the end of the daf, the rabbis introduce gatehouses - not the usual gatehouses which are structures used as watchtowers, but gatehouses that are actually houses which serve as passageways between two courtyards.  

I begin to wonder about how many of these circumstances are based on actual questions.  More and more I am assuming that many of the examples used to flush out practical halacha are actually hypothetical, philosophical extensions of arguments.  When debating these issues the rabbis are able to better understand how the law might be applied, and thus they create more precise definitions.

It is said that the use of law is like using a large paint brush to paint a delicate work of art.  The law is broad and blunt, while individual circumstances are specific and unique.  How do we ensure that such a clumsy tool will serve its purpose?  The rabbis' exhaustive debates allow us to have greater confidence in the applicability of halacha in unique situations.  

Looking at these ancient debates from a modern perspective, however, suggests that our Sages were not able to cover all possible applications of the law.  We have to extrapolate from what they have ruled in the past.  The introduction of anti-slavery, relativism and feminist thinking, for example, challenge some of the most fundamental assumptions used to frame the thinking of our rabbis.

The question is often posed as "do we throw the baby out with the bathwater?".  I would suggest that the more challenging question is HOW do we apply ancient halachic concepts to modern thinking.  Of course, rabbis have been hard at work at answering this question for hundreds of years.  But for me this is a relatively new and exciting endeavour.