A discussion is apparently going on to define “classical” music as opposed to other genres. This morning’s Today programme on BBC Radio 4 invited Debbie Wiseman and Nitin Sawhney to give their views, and Ms Wiseman proposed the most outrageous – and clearly erroneous – definition, perhaps as a provocation, or perhaps she believed it. Who can say?

Whichever, she said that “classical” music was fully notated by the composer and unchangeable. Mr Sawhney challenged this with the examples of J S Bach and Beethoven, who were both great improvisers as well as composers (according to MS Wiseman, this would not be classical music). Perhaps there wasn’t time for her to elaborate what she meant more precisely, but the examples of improvised music within the classical canon are legion. Almost all concerti for solo instrument and orchestra from Haydn up to the time of Beethoven included a cadenza where the soloist could show off his/her expertise at improvisation. Later composers have usually provided a cadenza for the soloist to perform, but should this change determine that Mozart, for example, is therefore not a classical composer? As late as the 1830s, it was common for singers in opera to improvise around the notes that the composer provided, and show off their skill.

In the twentieth century, composers such as Lutosławski wrote aleatoric pieces, in which although each section, and for each instrument, was precisely notated, the leader of the group, whether a conductor for a full orchestra, or a member of the ensemble, would determine when each instrument would begin and end its performance of the individual sections, so that performances could be radically different from each other, and in ways that the composer could not always have imagined. According to Ms Wiseman, these pieces would not be “Classical”.

There are also pieces in which the composer writes short sections, which may be performed in any order, and any number of times, and others in which the precise pitch, tempo and/or dynamics are not specified, but only relative to each other. Are these not within the “Classical” tradition?

And the word “Classical” itself has changed its meaning. Originally, it meant the Western music written between around 1750 and 1830 (both dates approximate). Earlier music of the 18th century was termed “baroque” and “rococo”, and later came the Romantics, usually starting with Chopin, Mendelssohn and Schumann. Now, “Classical” is opposed to “Popular”, although both terms can be subdivided as often as you like, so that they become to some extent meaningless.

And while we’re at it, why is all music now referred to as “songs”? The clue to “song” is in the word – it’s related to ‘sing’ – and if there are no voices, then it isn’t a “song” (unless you further specify ‘without words’ as Mendelssohn did, for piano pieces written in a particular form, often simply a tune with an accompaniment).