Email Capitalization: "Hi Michael, please bring..." or "Hi Michael, Please bring..."

In an email, if I don't put a new line after the heading, how am I supposed to capitalize the next word?

With a new line, it's straightforward:

Hi Michael,

Please bring the books.

But without one, is it:

Hi Michael, Please bring the books.

or:

Hi Michael, please bring the books.

I would appreciate sources citing a related rule.

Solution 1:

There are no hard and fast rules for such E-Mails, even if you are sending them to a colleague. Mostly because of emails being the recent phenomenon compared the the language in itself, I would use the same rules/sense that I use for writing letters. Personally, for a one liner, I would rather just start off without the salutation. And since I am including 'please', it is going to be courteous too. Eg:

Michael, please bring the books.

This way I don't have to worry about capitalizing the second word. But, if you'd like to use a second line, you should capitalize the starting word as suggested by the Purdue online writing lab article, which suggests:

Use standard spelling, punctuation, and capitalization.

and the standard capitalization rules (rule 12) and also this source suggests that 'Hi Michael' is correct and should be followed with capitalization of the next word when the next words starts off in a new line. Here is a book: Handbook of Business letters which suggests similar reasoning on page 50 along with its sample examples there. Here is another source that adds to the practice of capitalizing the first word if we start off with another sentence.

Solution 2:

To my knowledge, the only relevant "rule" is to begin the first sentence after a salutation on a new line (and capitalized):

Dear Michael, (or Dear Mr Smith: for more formal settings)

Please bring...

This applies equally to email and regular mail, so if you're looking for a rule to follow, I would follow the established convention.

I know that doesn't answer your question directly, but here's the thing: If you're starting the first sentence on the same line, you're kind of deviating from the rules from the get-go. In that case you're not likely to find a source that says: "Here's the rule to use when you're breaking the rule..."

If you want my 2 cents: I would capitalize the first sentence after a salutation regardless of which line it was on.