I don’t really have any evidence other than that an otherwise reputable prof told us this. I believe he said that we knew what Frost’s intentions were because of his notebooks and/or his supervision of the original publications of the poem.
Here is a link to the poem, anyway. http://www.robertfrost.org/indexgood.html
Under “Choose a Poem,” choose Stopping by woods.
I forgot to say…the difference between the two lines is more apparent if you say them out loud, especially while reading the whole poem–in that poetic way that people read poems out loud, if you know what I mean.
I know this has already been covered, but I want to make it clear: The single space after a period is not a new rule, it’s always been like that. Typesetters have never, from Gutenberg onward, used double spaces at the ends of sentences. The double spaces were only used when typewriting because typewriters are so bad at spacing their text.
Since computers can space things correctly, there is no need for extra space. The period character includes some space, so when it adds to the spaceband, you do get a bit more space after a sentence than you get between words. It looks best that way.
This question has pretty much been resolved in any printing and writing industry with a concensus for one space.
As Saltire said, it’s always been this way. As with so many other things we learned in school, we were not taught that there were other ways to do things. We were only taught to type the two spaces after a period because that worked on typewriters.
However, that being said, whether to use one space or two spaces is and will always be a style issue.
Decide what style you want to use and go with it. Or, if someone else is dictating your style (your company or your editor), do it according to that style.
The best thing about learning to use only one space after a period is that you get to type that many fewer characters. When you’re typing 200 pages of text, that’s a lot of space you don’t have to type!
Here are some online resources if you want to research further:
[ul]
[li]http://www.raycomm.com/techwhirl/spaceperiod.html (from a mailing list dedicated to technical writers and writing)[/li][li]http://www.grammarlady.com/faq.html#28 (The Grammar Lady)[/li][li]http://www.nas.nasa.gov/Groups/TechPubs/StyleGuide.html#HDR86 (from a branch of NASA)[/li][/ul]
Also, the following print style guides all advocate using only one space after a period:
[ul]
[li]Chicago Manual of Style, University of Chicago Press[/li][li]Microsoft Manual of Style for Technical Publications, Microsoft Press[/li][li]Read Me First! A Style Guide for the Computer Industry, Prentice Hall[/li][li]Gregg Reference Manual, McGraw-Hill[/li][li]Associated Press Stylebook and Libel Manual, Perseus Books[/li][li]Lapsing into a Comma, Contemporary Books (by Bill Walsh, Copy Desk Chief at the Washington Post)[/li][/ul]
Given time, I’m sure I could give you more references, but that’s enough for a starter set.
Go forth and type fewer keystrokes!
Jeyen
Technical Editor and Writer
Argh! I always misspell consensus and then notice later.
Please forgive.
Go ahead and continue using a double space after periods. At the moment, they’re not handing out citations for this and if enough people continue doing it, the manuals of style will eventually say something like “Use of a double space after periods is gaining acceptance…” in the same way ain’t has begun showing up in dictionaries. I feel that the extra space after a sentence helps create a more pleasing minor “break” or “rest” between sentences, in much the same way that a double space helps create a break between paragraphs. It irks me a little that there is a group of people sitting at a conference table somewhere telling me how many spaces I can use after a period.
My first indication the spacing thing was happening was using MS Word with the editing marks. It suddenly started putting fuzzy lines between sentences, telling me 2 spaces was wrong. I disagreed from what I was taught.
However, I do not conform to traditional quoting, I use the logical method of inserting the punctuation where it belongs by meaning. Bob said, “Go tell it on the mountain.” Period goes inside the quotes. However, Bob is a “blabbering idiot”. Period goes outside. This is a holdover from typewriters, too. Punctuation marks like periods were more fragile than full letters, and putting them on the end of lines when typesetting had the effect of sometimes breaking them off. Thus inserting the punctuation inside the quotes. Since we now do not have to worry about that, I am reverting to what is more meaningful. (I do the same thing with parentheses.) It looks like this (much better, I think).
Given that I’ve already adjusted my style for those, I will perhaps try to learn to single space between sentences.
One other thing that confuses me: I thought I learned that for many words ending in “l”, you doubled the l when adding “ed” or “ing”. But spellcheck always catches those and tells me it’s one l. My dictionaries seem to agree with spellcheck. Where ever did I get that notion? It drives me batty. (See, you double the “t”. Why not the “l”?)
If you select Options from the Tools menu, select the Spelling and Grammar tab, and click the Settings button, you will find a dialog that lets you choose how many spaces you want after periods: one, two, or however many you damn well feel like today.
Can’t we all just get along? How 'bout this compromise: use a “wide” space (m-space?) instead of two “narrow” spaces (n-spaces?). Option-Space on a Mac, I think. Not sure on a Winbox.
Also…
I’m with you here!
Irishman:
The general rule, I believe, is that you double the consonant when the emphasis is on the syllable that contains it. TRAveled, reFERRED.
And FWIW, I use one space after periods, and I put punctuation outside the quotes or parentheses when I’m not quoting an entire sentence.
I loathe single spaces after periods at the end of sentences and will never ever type that way. I think it looks terrible and to me, there IS a very noticeable difference. I don’t bother typing ALT+0160 when typing these posts, though, which would prevent the coding from changing my two spaces to one.
Re Robert Frost: my whole image of that poem is ruined. It is one of my favorite in all literature and I always thought the line was “The woods are lovely, dark, and deep” - not “… lovely, dark and deep.” The whole nuance becomes something entirely different. I plan to dig out my copy when I get home to see how I could have possibly misread it all these years. 
I’m a sports editor who works with a lot of stringers who aren’t necessarily trained in journalism. I feel like a gardener ripping out weeds as I scan through their stories, ripping out the second space after the period. I wouldn’t mind having a standard – one space or two, it doesn’t matter, as long as it’s consistent.
**Sno[sup]5[/sup]py, if it’s really that much work for you, you can probably do a “find and replace” to change all instances of " " to " " (that’s “space space” to “space”, in case that doesn’t turn out right).
Balthisar, I don’t think that Microsquish has a long space character, or if it does, it’s not in the ASCII character set. It might be in Unicode or one of those specialized character sets used by word processors, though.