View related sites
I was today years old when I found out that Swahili time is benchmarked at 6:00 a.m. and 6:00 p.m., meaning Swahili clocks look like this:
Beyond just looking at this with interest, it begs the question: how do we meaningfully move between Swahili time and English time?
Imagine it’s sunrise. In Kenya and other Swahili-speaking countries, the times for sunrise and sunset are almost identical year-round (mind-blow number two) which means getting up at sunrise might not even require a clock. In an English cultural sense, sunrise time can be measured at what is for us 6:00 a.m., and the day “starts” roughly halfway through the night at midnight. There is then a second benchmark halfway through the day, which is midday.
It doesn’t have to be this way though. If you choose instead to benchmark at sunrise and sunset, you might then call sunrise “12 in the morning,” as is usual in Swahili. When you consider this further, labelling 6 as “midnight” and “midday” seems perfectly reasonable in this context, given that 6 is mid-way through 12.
It’s remarkable how difficult this can be to grasp at first, and reminds me how complex telling time (an intangible measure that we only really understand in relation to space and ourselves) can be. Adding the idea of time zones shows this: without saying where, specifying a time, a day and a year (e.g. 6:54 on 3rd Feb 2001) only narrows the window down to 24 hours. Measurement systems, including numbers themselves, only represent or express in one particular way the abstract thing being measured, which always makes my brain hurt.
So why the clock juxtaposition? If we are so used to “seeing” the hands and reading the marks without numbers (as research suggests we can), then this suggests an intriguing possibility: that this clock is designed to be “read” backwards for those who need to “translate.” And indeed it seems this is the story: this is most likely a tourist clock, or at least one produced to help non-Swahili speakers.1 Swahili speakers (and speakers of nearby African languages that tell time similarly) use standard clocks, set with the hands in the standard position, and add or subtract six hours when they read the time.2
For those among you with a particular religious background, a bell might have been rung here (pun wholly intended). The Apostles observed the Jewish custom of praying at the third, sixth, and ninth hours, and at midnight (Acts 10:3, 9; 16:25); the Liturgy of the Hours is a ritual consisting of a set of prayers at particular times of day which survives from this period, and follows the Roman convention of the "first hour" being – you guessed it – (approx.) 6:00 a.m.:
Dividing the day and night into the period 6:00 a.m. – 6:00 p.m. and 6:00 p.m. – 6:00 a.m. feels very natural to me; even within my household, however, this is not consistently the case. How do you visualise slicing the cycle of day and night? Does the concept of dividing into halves even make sense for you, or do you feel more that "eight hours of sleep, eight of work, and eight of play" feels more like your sense of a 24-hour period?
Time is not only complex and cultural, but can be very controversial. Have you heard of the Hopi time controversy? In the 1950s, a claim was made by a researcher named Benjamin Whorf that the Hopi people (native to north-eastern Arizona, USA) had no concept of time – specifically “no general notion or intuition of time as a smooth flowing continuum in which everything in the universe proceeds at equal rate, out of a future, through the present, into a past..."4 Various myths about this persist even to this day, and debate has raged ever since, with most of the arguments being linguistic ones: for example, Whorf suggested that Hopi units of time are not represented by nouns, but by adverbs or verbs, proving his hypothesis; a thorough refutation by Malotki (1983) suggested that the evidence does not support this view, but that the Hopi -ni suffix marks the future tense, and that Hopi has a future-nonfuture tense system. Malotki also argued against both of Whorf’s main points, stating firstly that the Hopi language has an abundance of terms, words and constructions that refer to time, and secondly that the Hopi conceptualize time in analogy with physical space, using spatial metaphors to describe durations and units of time.5
While it is true that there is no word exactly corresponding to the English noun “time,” Hopi employs different words to refer to "a duration of time" (pàasa' "for that long"), to a point in time (pàasat "at that time"), and time as measured by a clock (pahàntawa). It includes terms for an occasion to do something (hisat or qeni), a turn or the appropriate time for doing something (qeniptsi (noun)), and to have time for something (aw nánaptsiwta (verb)).6 All these rich ideas, expressed in linguistic discreteness, contribute to an understanding of time that is multi-layered, which research suggests is very important in development of time concepts for learners grappling with time.7
In particular I would be intrigued to put a double-number-line clock like this on my wall and see what happens…
Join the conversation: You can tweet us @CambridgeMaths or comment below.