This is one that’s gone, if not exactly viral, at least mildly infectious on Facebook, with writers and editors debating the pros and cons of single or double spaces after full points in manuscripts and word-processed copy. As a sometime editor, I can tell you that it introduces problems into word-processed copy that require extensive fixing at the editorial stage to produce text that’s fit to print. So why do so many writers still do it?
The practice dates back to the days of monospaced text from manual typewriters, which unarguably did make text with single spaces after periods harder to read. Actual typesetters for print had looser conventions on the issue for long before this, but most adhered to single spaces after full points. However, the teaching practices inherited from these continued long after monospaced typing had died out. And multiple generations of writers have grown up in this tradition, and defend it to the hilt.
The Chicago Manual of Style Online is fairly unequivocal on this. “The view at CMOS is that there is no reason for two spaces after a period in published work,” it says. “Many people were taught to use that extra space in typing class … But introducing two spaces after the period causes problems.” The Economist concludes that it’s mostly a matter of house style.
Others are a little more forthright in their opposition to double spacing. “If double-spaces are used after periods, it tends to make the paragraph look like it’s been blasted with buckshot (or needless space),” argues IdeaBank Marketing. “Typing two spaces after a period is totally, completely, utterly, and inarguably wrong,” asserts Farhad Manjoo in Slate, and then marshals many arguments to prove it. And from a practical point of view, this surely is the correct analysis. However, it’s also one that, as many writers argue, is relatively easy to fix with a mass search-and-replace or other workarounds.
Overall, though, it seems to be people who produce text who are arguing in favor of the double space, and people who process it and otherwise work with the finished result who are arguing for the single space. Draw what conclusion you like from that. And opinions invited.