Is classical influence essential to prog rock?

There's something I've become more and more confused about regarding the exact definition of "progressive rock" recently, in part because my own knowledge of music theory is very basic and I'm not sure exactly how to test the argument in practice.

I get the impression there's two contrasting definitions of the genre/movement. The first defines "progressive" as just thinking outside the box in terms of style and theme, progress here meaning moving the genre forwards and not really being a specific style. The second one has "progressive rock" refer to progress within a composition, as in abandoning the cyclical verse/chorus song structure of pop/rock tradition in favour of a classically inspired sonata format dominated by linear forwards progression. (I think this is the definition J. Derogatis uses in his book Turn On Your Mind: Four Decades of Great Psychedelic Rock) Under this definition bands like ELP, Genesis, King Crimson and Yes would be prog. However, groups like Hawkwind, Jethro Tull or Pink Floyd would at best have ten songs each that qualify as prog... instead being classified as "art rock" under this definition. (a categorization I'm still not sure exactly what means - when I first encountered it I saw it used as a synonym for progressive rock, but now I'm far from certain as you can see)

The plot thickens: Then there's the question of how much stuff like Captain Beefheart or much of Krautrock would count as prog under the second definition. Its classical influences come from very different sources (Stravinsky, Stockhausen, Varese etc.) and is more about deconstructing the building blocks or structural ideas behind music than constructing lengthy complex pieces of music.

Can anyone here clear things up for me? I'm curious to find out how the genre categorizations of "art rock" and "progressive rock" have evolved historically, in specific how much influence from classical music has been an essential part of the latter. Should mention that Derogatis' book uses the classical influence to draw the line between progressive rock and psychedelic rock instead, the latter I'm certainly fine with regarding as a "cultural movement" at least as much as a style of music.

Certain fans of the genre seem to want to make 'progressive rock' broad to the point of meaninglessness. Not every type of "creative" rock music is prog. Captain Beefheart is almost never considered prog outside of this site.

Oddly enough other fans of this genre want to make it narrow to the point of meaninglessness...

I completely forgot what Manuel mentioned, that quite a few of the musicians initially classified as "progressive rock" rejected the categorization! (also Jethro Tull among them) Which is probably relevant to the discussion.

I personally define progressive rock as "a complex form of rock music that fuses rock with non-rock genres such as jazz, classical, and folk."  I think that this definition includes a wide variety of bands while also being sufficiently exclusive: it accommodates every sub-genre on this site but also sets boundaries, i.e. you can't just play a folk song with electric guitar and drums and call it prog (because of the required element of complexity) but you also can't just write a complicated rock song and call it prog (because of the required element of non-rock elements in the music). 

This definition isn't perfect, and of course strict definitions like this really don't do justice to the way humans categorize things, but I think it is the best short explanation you can give, and I find it helpful to use when explaining to people what progressive rock is.  It doesn't include every band on this site but it covers most of them.  The article about prog posted on on PA (linked from the PA homepage) is a very good long-form explanation of the elements of progressive rock, in my opinion.

So in short, no, I don't think classical elements are needed to classify a musical piece/artist as progressive rock.  But I do think that non-rock influences (classical or otherwise) need to be present.

No, but it helps.

Toaster Mantis wrote: But yes, the "no prog without classical influence" crowd I've discussed with in person do indeed insist that ProgArchives is way too inclusive whenever the subject comes up.

Not surprising somehow, but who exactly are these numbskulls?   Sounds like some fifteen year-olds who heard Yes just last year and assume if something is complex and arranged it must be based on Classical.  

I would say Classical helps in the way that all musics help Prog; which is to say it doesn't hurt.  

Edited by Rick Robson - December 28 2013 at 07:22

rogerthat wrote: I think you could start with that Dave Brubeck piece I mentioned, or the album as such - Time Out.  More so because Brubeck is an acknowledged influence on prog rock.   As for the difference between soul and R&B, I am not very clear myself because my interest in either does not begin before at least the late 60s whereas the differences were probably laid down a bit earlier.  I reckon R&B is the older genre and soul is essentially a more vocal based and gospel influenced variety of R&B.