It's time to bury the comma

Today, the dot (.) is used as decimal separator in the English speaking world while the comma (,) is used in most other countries, such as continental Europe and the Nordic countries [1]. This difference can be an annoyance as well as a source of potentially serious errors. Therefore, it would be beneficial to once and for all replace the ‘continental’ comma usage with the technically and scientifically more widespread dot usage. In this text, five proper reasons will be highlighted.

Firstly, it is illogical that specifically the decimal sign is different across the world, when almost everything else connected to maths stays the same throughout much of the globe. The rules of arithmancy, algebra and calculus are the same (e.g. independently of geographical location, 5-2=3), the operators (i.e. mathematical symbols) are the same and the same stays true for the way we write numbers (at least in Western countries). Then, it seems logical that also a sign as vital as the decimal separator should remain the same.

Secondly, most Nordic and continental Europeans are, already, quite accustomed to the Anglo-Saxon way of splitting decimals from integers: look at pocket calculators, thermometers, scales, voltmeters et cetera… Then, it would also be much less confusing for children if they could write the same symbol (i.e. ‘.’) on paper as they see on the screen of their calculators.

Thirdly, a whole lot of other things have been standardised, at least throughout the European Union. For example, the period of daylight saving has quite recently been standardised this way. The other most well known example, at least for Britons and the Irish, is the official adoption of the SI system replacing the foot and yard with the metre, the pounds per square inch with the Pascal, the pint with the litre and so on. Then, one may think, the rest of Europe, could give their commas up.

Forthly, by avoiding using different decimal signs, it would be possible to avoid mistakes. For example, it’s definitely safer to ignite 5.000 g hydrogen gas than to ignite 5,000 g. People accostomed to one usage may – quite easily – be confused when having to switch to the other.

Fifthly, certain computer programs have their own configuration concerning the decimal separator, and hence do not use the standard configuration defined in the operating system. So, on the same computer sometimes the comma should be used and sometimes the dot is demanded. Confusing? Risks making mistakes? Probably.

Another complication is that the sign not used as a decimal separator is often used as a thousands separator (as in 5,000 g). This makes it all even fuzzier. However, this is a relatively small problem in scientific contexts since powers of ten or prefixes are usually preferred (as in 5 ∙ 10³ g or 5 kg). Besides, since the advent of computers this confusing usage has luckily somewhat declined. Still, this could be an source of consternation for people dealing with, for example, economics.

So, the bottom line is that it would certainly be logical to fully abandon the comma usage as decimal separator. In scientific contexts, the shift has largely already taken place; I always use the dot as decimal separator, also when writing in Swedish. I believe society as a whole would benifit from a complete change. Besides, it is easy to implement; only the textbooks in school need to be slightly altered. So let’s bury the comma. Long live the dot!

References

[1] Decimal separator. Wikipedia. http://en.wikipedia.org/wiki/Decimal_separator (reviewed 18th of May 2009).