Halachic Standards of the Chazon Ish and the Disparity between Actual Scientific Findings and the Determination of the Halacha


  • Uri Redman


The halachic dispute among the authorities of the past generations regarding the correlation of halachic standards from the Torah (“shiurim”) with standard units of measure commonly used today, arises from a basic question: are halachic standards given in terms of natural measures (e.g., parts of the body, fruits, eggs, etc.) an attempt to express absolute units using the limited means of the ancient world, or are they themselves the true standards, and thus subject to change with time and place and even subjectively dependent on the individual? This dispute has been understood to have arisen from diverging community traditions; moreover, some view it as a dispute between the written word and the popular tradition (“minhag”). In this paper we suggest that the opinions of the Chazon Ish and Rabbi Chaim Naeh are two comprehensive approaches towards reconciling the mismatch among the various halachic units brought down by the sages, both within the Halachic framework, as well as vis-à-vis presently known values in nature. While both these approaches are based on halachic sources and various
accepted traditions, their main innovation lies in each one's attempt to create a single consistent rule for halachic standards which actually depart from current common practice.
The viewpoint of the Chazon Ish, as described in his book Handbook of Halachic Standards (“Kuntros Hashiurim”), reveals an attempt to deal with central issues in the halachic world, e.g., an opposition to reliance on sources extraneous to Halacha – even physical, archaeological or scientific – for rendering halachic decisions. His opposition to adopting absolute methods of measure for halachic standards has been consistent, despite the development of modern methods of measurement.
Furthermore, the Chazon Ish understands the shiurim as natural estimates, and their estimation for the purpose of establishing a “shiur” is what empowers Chazal in their role of passing on the Halacha throughout the generations, not only as the
authoritative expounders of the words of the sages, but also as a binding authority, similar to a decision of the High Court – when confronted with contradictions among the various shiurim, and additionally, even as an authority for creating and establishing new standards for mitzvot from the Torah. On the other hand, in the opinion of Rabbi Chaim Naeh, the role of the sages regarding Halachic standards is purely explanatory, enabling the discovery of the standards that Moses received
on Sinai and their formulation in terms of modern units of measure.
As an introduction to understanding the opinion of the Chazon Ish, this article reviews his unique approach towards understanding the concept of “natural world changes” (“hishtanut hatevaim”), as well as his opinion regarding the relationship
between the halachic units described by natural objects, in contrast with those derived numerically from fruits or parts of the body.



How to Cite

Redman, U. (2018). Halachic Standards of the Chazon Ish and the Disparity between Actual Scientific Findings and the Determination of the Halacha. BDD, 34, 7–24. Retrieved from https://biupress.org/index.php/bdd/article/view/2



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