Do you insert one space or two after a period? Many people are surprisingly (even absurdly) passionate about their preference, yet this seemingly minor issue is not nearly as cut-and-dried as it may at first appear to be.
A Little Background on a Longstanding Debate
The one-space-versus-two controversy has raged throughout the history of printing. As Avi Selk notes, the debate can even be traced back to the Declaration of Independence and to early printed versions of the Judeo-Christian Bible. A quick online search reveals that it continues to be a hot topic.
For many years, I believed (and even said in this blog) that the two-space convention arose because typewriter fonts lacked proportionally spaced characters. According to this argument, all letters, numbers, and symbols used up the same amount of real estate on the typewritten page, leaving more space between skinny characters, such as the letter “I” and the number “1,” than between wider characters, such as the letters “M” and “W.” To ensure that readers could easily spot the end of one sentence and the start of another, people using typewriters inserted more space after end punctuation to distinguish the space between sentences from the space surrounding narrow characters.
I have since learned that this theory is full of holes.
Another closely related but equally specious belief held that published books have always used only one space after periods. Not true.
In an article appearing in its Shop Talk series, the very reputable Chicago Manual of Style (CMOS) dispels these myths and others that commonly appear in discussions about spacing after end punctuation. (If you’re looking for an even deeper dive, this article by an artisan book publishing company makes a compelling case for the fact that the choice to use one space or two is largely arbitrary, having little to do with font spacing, typewriter conventions, or the history of printing.)
The Two-Space Camp
Most (but, as we will see, not all) people who favor two spaces learned to type on a typewriter. A rule acquired many moons ago has, no doubt, become deeply entrenched and is difficult to shake. Nonetheless, those who stick to it may be doing so not merely out of habit or even sheer stubbornness: some insert two spaces because they believe the visual cue at the end of every sentence renders their texts more readable.
In 2018, our “two-spacers” gained meager support from researchers who argued that reading comprehension improves slightly with the additional space. Though not terribly compelling, that study nonetheless elicited some strong opinions, as reflected in this article in the Atlantic.
The One-Space Camp
Those who favor one space most likely learned keyboarding on computers and were taught to use only one space. They believe two spaces are unnecessary and even distracting.
Some “one-spacers” can be extremely arrogant in their dismissal of those who favor two spaces, as evidenced in this article, enlightening not only for its lack of nuance but also for the heated responses expressed in the comments.
So What Do I Advise?
For the past forty years, I’ve inserted only one space after sentence-ending punctuation. When all is said and done—and even after we dispense with the false information and historical myths swirling around this issue—we can’t make a very strong case for holding on to the two-space convention that many of us learned decades ago.
That said, if you feel strongly about using two spaces, be consistent throughout any single document. Readers may become distracted (if only subconsciously) by spacing that fluctuates, and text that is consistently spaced is more aesthetically pleasing.
It’s also helpful to consider other factors:
- For enhanced readability, if you choose a word processing font that is monospaced instead of proportionally spaced—such as Courier New, Lucida Console, and Andale Mono—then you may gain some readability by using two spaces.
- As far as I know, most (if not all) style books advocate the one-space approach. However, if your workplace has an in-house style manual or adheres to a particular style (e.g., MLA, APA, AP, CMOS), then you should stick to the guidance provided by that resource.
Old Habits Die Hard
If you learned to type on a typewriter but now prefer using only one space, you may find it challenging to shed the deeply ingrained two-space habit. Word processing software programs provide helpful tools:
- The CMOS article reminds us that we can ask Microsoft Word to flag sentences followed by two spaces. Simply navigate to File > Options > Proofing to adjust the settings for Word’s grammar checker. Once in Grammar Settings, scroll down to Punctuation Conventions to find Space Between Sentences. There you will have the following options: “don’t check,” “one space,” “two spaces.”
- If I’m using a proportionally spaced font, I use the global find-and-replace function to make sure I am consistent: I search for all instances of two spaces in a document and replace them with one. The process takes about three seconds.
(To read about another hackle-raising issue, head over to the post on the Oxford comma.)
Copyright 2002 Get It Write. Revised 2018, 2023.