Why is a novel typically several hundred pages long, and a typical play or a movie around an hour and a half in duration?
Yes, there are many novels, plays and films that are longer or shorter, but there seems to be a remarkable adherence to this statistical norm.
My theory is that there is only a certain emotional bandwidth in any medium, and that these lengths represent the minimum informational budget required, using reasonable economy, to sketch out a certain kind of arc of human experience. In a short story or a half hour TV drama, there isn’t quite enough time to render a complete enough stand-alone portrait of a protagonist and his or her world to convey a powerfully transformational experience for reader or audience.
I just read a glowing review of Abel Gance’s Napoleon. 330 minutes (5 1/2 hours). http://bit.ly/GXV0iR Apparently, You Had To Be There.
The first thing that came to mind when I read this post is the lament from Billy Joel’s “The Entertainer”:
I am the entertainer,
I come to do my show.
You’ve heard my latest record,
It’s been on the radio.
Ah, it took me years to write it,
They were the best years of my life.
It was a beautiful song.
But it ran too long.
If you’re gonna have a hit,
You gotta make it fit–
So they cut it down to 3:05.
I’d say it’s because an hour and a half is a convenient amount of time to ask a human to devote to an entertainment activity. A play has to be self-contained due to the nature of the medium, but you can take breaks from a novel, so it can afford to be longer since the person reading it will break their reading time into conveniently-sized chunks anyway, and an author will help by providing natural stopping points in the form of chapters.
A TV show operates by the same principle, it has half-hour or hour-long “chapters.” The true length of a television series is show length * number of episodes, and keeping that in mind you can see that a TV series can match or exceed the length of your typical novel.
~1.5h is a good duration to sit down without having to get up for restroom or water/food lol.
I believe that the length of time here is culturally determined. A russian might expect a movie to be longer, for example. The 90 minute movie thing I am pretty sure has been determined by hollywood through experience, not theory.