Classical Syndrome Checklist:
Black clothing covering over 80% of body (White shirts for men.)
Performers remain in a fixed position for each piece.
Improvisation not a feature.
Music played has an intellectual, theoretical ground.
Instruments primarily acoustic.
Electronic sound effects not a major component of produced sound.
Musicians expected to be sober, not on recreational drugs.
Performers evaluated, in theory at least, on the sound they produce, not their styling, dance moves or simulated sex routines.
Major focus on sound produced, not actions of audience members.
Audience listens to performance in silence.
Audience members still.
Audience sitting.
Audience expected to be sober, not on recreational drugs.
I started this is in humour but it seems that with a little more refinement and extension we could say something like, “If it’s got more than 6 of these symptoms then it’s classical music”.