[TheOtherHobbes]

None of the above. It's dissonance as a language - traditional expectations of how the harmony develops being stretched, subverted, warped, and so on. For emotional effect.

There isn't really a modern equivalent, which is more or less the point. Not even jazz, which is distantly related.

But you can get a remote sense from something like Damien Hirst's Verity Statue, which starts from some familiar expectations of public sculpture and subverts and undermines them.

https://www.youtube.com/watch?v=2jrvX2ZrDvk

The difference is Hirst evokes horror and a Capitalist Gothic aesthetic.

Schubert is superficially more reassuring now. But at the time he was influenced by what used to be called the Sublime - which doesn't just mean excellent as it does today, but used to mean a complex state of emotion and experience that was so intense and rich it was overwhelming.

That's what's buried in Schubert's use of harmony and dissonance.