If punctuation marks always go inside quotation marks, then why is the period outside the quotation marks in Rule 5?
The period is placed outside the quotation marks in that sentence because I did not want to imply that possession is indicated by an apostrophe followed by an “s” and then a period (i.e. “John’s. books”). I think that my intentional disregard of the standard practice of including punctuation within quotations helps to avoid confusion in this case, without adding any ambiguity or awkwardness. In fact, I’ve always thought that the standard practice in this case can lead to confusion in many, many sentences, especially in direct quotes taken from the middle of a sentence. Putting a period within the quotation marks just because a “rule” tells us to can in certain situations imply that the original author of the sentence had a period in that spot too. I think that EVERYTHING (except ellipses) within a direct quotation should be identical to original author’s text. That said, ALL grammarians that I have encountered have supported the rule that ALL PUNCTUATION GOES INSIDE QUOTATION MARKS. It
