The Mozart A Major Sonata (K 331)?

It's a complicated question. Warren Darcy has a great discussion about this piece in his book "Elements of Sonata Theory"

Sonata-allegro form is the most typical of five common forms in sonatas as defined by Warren Darcy and James Hepokoski. we see this same kind of formal construction in a few early sonatas by Couperin and Haydn.

Is the formal construction we call a sonata independent of the pieces that established the definition of that form? I think not. Sonata has a circular definition, a sonata is defined by what composers call a sonata (not by what theorists call a sonata). I think we should call the piece by the title Mozart gave it.

Ultimately I think this is the kind of questions theorists love to debate and performers mostly ignore. I'm curious now as to how someone would play this piece differently if were no longer called "sonata". Perhaps a listener might listen with different expectations.

The term Sonata is usually used to denote works for solo instrument, or for piano and another instrument. While the majority works in this genre, in normal practice, usually contain a first movement sonata-allegro form, there is nothing set in stone (obviously) that dictates one must be present.

It seems to be more a matter of the medium (instrumental) and the number of performers. You will find that Beethoven's Sonata in Ab, Op. 26 and his Sonata in C# minor, Op. 27, No. 2 are also exceptions to the "normal" form.

The origin of the term "sonata" comes from "canzon da sonar" or to be sounded on an instrument in contrast to "toccata" (keyboard), and "cantata"(to be sung).

Musician, composer, teacher.

I don't have anything to add to the other explanations, except...

most of Scarlatti's works are referred to as sonatas - most of them are only one movement and not even close to sonata - allegro. In fact, Scarlatti himself referred to then as "essercizi."

I guess the definition is rather more flexible than we might expect.

But of course we should still call it a sonatata...opps, I mean a sponata...Oh, shucks...this keyboard...well....

let's just say that keeping the music publishers from feeling outdated, we need to flurry up and let it all dust down.

Wait ....hand me your copy of the Mozart Sonatas, please, and open it to K331 ......I have a rubber stamp just for this occasion: it says, discovered by BLH, May 2008 / not a sonata / oops

xxx

Many composers call one of their pieces something it actually isn't ... it's like the "Alpensymphony" from Richard Strauss.. it's not even close to what we understand as symphony..