The Oxford Comma: The dispute settled

I am here to permanently settle the Oxford Comma dispute.

You didn't know there was a dispute? Or even what an Oxford Comma is?

For shame. For shame! Read on.

The Oxford Comma is about clarifying elements on a list. Here is a sentence with a list where the Oxford Comma is missing:

Tom saw ministers, Mark and Henry.

That can be interpreted two ways: Tom saw ministers named Mark and Henry, or Tom saw ministers, and Mark, and Henry. In the first, the ministers are Mark and Henry. In the second, the ministers are not Mark and Henry. So how do you know which is correct?

You add the Oxford Comma, that's how. An Oxford Comma is just the comma that is placed just before the "and" in a sentence with a list. Our sentence, with an Oxford Comma:

Tom saw ministers, Mark, and Henry.

There's only one interpretation of that sentence: Tom saw some ministers, he saw Mark, and he saw Henry. Three different sightings. Boom. 

Now some sentences are more easily understood. Marcus ate beans, corn and avocado is highly unlikely to be understood to say that corn and avocado are types of beans. But if you develop the habit of using the Oxford Comma, the uncomplicated sentences will not lose or increase in ease of understanding but complicated sentences are likely to increase in that quality. 

Remember that the ultimate goal of writing should be understanding between the writer and reader. The Oxford Comma aids in meeting that goal. 

IMHO, anyway.