QUESTION

Chicago, IL

There is a fancy board game that makes use of a sand timer to limit the time in play (similar to how a chess clock measures the total time in play over the course of the game). Is it permissible to play this game on Shabbat? (What about chess clocks?) Nothing is being measured (30 seconds, 2 minutes), but the sand clock determines the duration of the game.

ANSWER

Although there is a general prohibition on Shabbat of medidah – measuring on Shabbat (SA OH 306:7, SA OH 323:1, MB 306:34), I think this is totally fine, for the following reasons:

1. As you indicate, it is not measuring a specific amount of the time. A person just has to finish their turn before the sand runs out.
2. Related to #1 – when there are two states – on or off, sand hasn’t run out or has run out – then that is not measurement. There are no markings on the device to show when it has reached half, or a quarter, or three-quarters.
3. I do not believe that the Rabbinic restriction on measuring applies to an abstract, non-physical entity like time. A sand timer doesn’t measure the sand, it uses sand to measure the passage of time. The thing itself – time – isn’t being measured, and it isn’t really a thing. This argument is also presented by the Tzitz Eliezer who writes (Tzitz Eliezer 3:10):

משום דאינו מודד כלום והזמן הוא דבר שאין בו ממש, ואינו משתעבד תחת ידי מדידה מעשית ולא קעביד מעשה לגמרי כשעורכו מאתמול והוא הולך מאליו

So, in short, I think it’s totally fine.

I should note that reasons 1 and 3 also apply to a chess clock – where the goal is to finish before the clock runs out and not to measure the time that a particular turn took – but reason #2 is not applicable. Chess clocks have a different problem independent of medidah (measuring), – which as noted likely not an issue – namely, that writing/notation of moves usually goes directly together with use of it, which puts it in uvda di’chol category and possibly an abstracted gazeirah shema yichtov (rabbinic enactment lest one come to write)/ shtarei hedyotot (reading business or other non Shabbat approriate documents).