I’m not asking Hamlet’s existential question. To be or not to be? To live or kill myself? It’s literal grammar.

To eat –> She eats.
To dance –> She dances.
To be –> She be.  She is.

The verb TO BE conjugates, or breaks down, into the form is when referring to a singular third party he, she, or it. She be sweet. She is sweet. TO BE morphs into are in the plural. They be sweet. They are sweet. 

In all its conjugations, the verb TO BE serves as a referential foundation in the English language. TO BE enables us to assign description and value to people, things, ideas.

The trees are lovely in the wind.
Trees = Lovely
TO BE would be impossible not to use in speech and writing.

But artful writing shouldn’t depend on this verb. You want to minimize its appearance. As a verbal equal sign, TO BE makes assertions that fall flat. Good writing carries momentum. Because verbs are action words, they propel the message and description forward.

Rather than take up a whole sentence just to say the trees are lovely (apart from poetic circumstances that ask for this declaration), you could say

The lovely trees sway and bow in the wind.

Now the verbs sway and bow paint a picture the are doesn’t.

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Here’s a clip from the post The Invisible Woman:

So-nyo, an elderly mother of four grown children, vanishes in the Seoul subways.

I could have written
So-nyo is an elderly mother of four grown children who vanishes in the Seoul subways.

The line I settled on runs on only one verb vanishes. I didn’t want to waste time and words stating what So-nyo is when I could show it while saying something more interesting or informative. My point is that she disappeared, not that she was an elderly mom of four.

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I dug up two written samples from my high school days just now. *Wrinkle nose*

The mathematical straight line whose end arrows stretch on to eternity is the prime example.  The line will always be at least a billionth of a millimeter off…

Twenty-five years later, I would say
The…line…serves as the prime example. It will remain at least….

Serves, stands, remains, runs are picturesque alternatives to is.

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James’ simple act of giving milk for the sick children is profound and laudable in its contrast to the headmaster’s pretentious and futile plans for the village.

Revise!

James’ simple, profound act of providing milk for the sick stands in glaring contrast to the….

The whole first sentence rests on the verb is. If you blip it, you are forced to retrieve a more interesting verb which in turn carries the writing forward rather than keep it static.

Circling back to our starting question, then:
when writing, it is better not to be.