Something true about me: I love being right, but I can tolerate being wrong. Sometimes. That’s how this project got started. A simple “water-cooler” conversation at work led to dogmatic proclamations regarding how many spaces properly follow a period. “One space only,” I proclaimed, feverishly forwarding a Slate article as incontrovertible proof. Case closed, I thought. Then one of my colleagues steps into my office, proudly holding his high school grammar book, circa 1995, confirming his assertion that two was actually the correct number of spaces after a period. Witnessing this exchange, one person smelled the beloved grammar book and declared it “old.”

I was undeterred. I consulted my own authority, The Chicago Manual of Style, 17th Edition, for additional validation and got it. “2.11 – Spaces, tabs, and hard returns within paragraphs. A well-structured electronic document will never include more than one consecutive character space.” Yes, Chicago, I love you. No gray area there, I thought.

Later in the week, I shared this delightful tempest in a teapot with my wife expecting chuckles, agreement. But she exceeded my colleague’s dogmatism with far less than a smelly grammar book: “two spaces is correct because it’s what I was taught.” How, exactly, to argue with that? “Sorry,” I said, “you’re wrong. I looked it up.” (Usually that’s an effective argument-settler. She’s a lawyer and a printbound authority can save the day.) But she re-doubled, stating the same position over and over as if I were our stubborn and ancient cat.

By now, I’ve become mildly obsessed, checking every possible reference for additional evidence to bolster my position. When many of us were younger, two spaces was indeed the rule, but there were mechanical reasons for this, based on how manual typewriters work. But maybe there was room for debate? Or at least some ambiguity?

And that leads us to this little website, twospaces.org. Feel free to email me (rob@twospaces.org) with your own first sources, smelly grammar book citations, and personal stories about this great sentence-ending bit of punctuation.