Hello, dear Gurus and Members!!

In the grammar book, there appears ergative sentences and middle constructions, exampled as below.
The scholars would say that ergative "The book didn't sell" and middle construction "The book sells well" are two different constructions.

But I have a doubt on that.
I assume that native speakers consider the two sentences as the same construction.
Do you feel the "didn't sell" and "sells well" totally different constructions?
Grammars and theories aside, and native's sense considered, what is the correct understanding?

ergative pairs

Peter closed the door. — The door closed.

I broke the glass. — The glass broke.

The wind shook the trees. — The trees shook in the wind.

I roasted the meat. — The meat was roasting in a hot oven.

middle construction

Butter cuts easily.

This book sells well.

Some paint washes well.

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In your ergative pairs, the second sentence is equivalent in meaning to a passive sentence - The door was closed, The glass was broken, etc. In your middle construction sentences, there is no exact passive equivalent.

There is therefore an underlying difference between the two classes. I imagine that most native speakers would not be aware of the difference. They almost certainly would not know the terms 'ergative' and 'middle construction'.
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Oh, I see.... I see....

That seems to be something I need to seriously ponder upon...

Thanks for the input, fivejedjon!!
After second thought...
On the passives of middle construction....
How about, "Butter cuts easily" into "Butter is cut easily", and "This book sells well" into, "This book is sold well"?
Aren't these passives that reflect the original sentences?
pructusAfter second thought...On the passives of middle construction....How about, "Butter cuts easily" into "Butter is cut easily", and "This book sells well" into, "This book is sold well"?Aren't these passives that reflect the original sentences?
No. If we say "Butter cuts easily", we are not actually saying that it is cut, merely that it can be cut.
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Oh.... That is so wonderful!!

Now, I see what this is all about...

Thanks so much, fivejedjon!!