Impressionism has scope. Most people can tell a [famous] Renoir from a Monet and would not think Renoir copied Monet (in general). The devil is in the detail, courts have too decide what is too close and what isn't, but it's very much 'I know it when I see it', I feel. Allowances to be made for distinctiveness.

I'm not a movie buff, I know a few films from Spielberg's oevre, but I've never seen anything that I thought was a copy of his style ... perhaps you have examples you feel are so close that 'a blind man on a horse' would see (sic) that they are copying Spielberg's style?

I like the change of tack though, would appreciate some more push back.

I'd like to stick with Impressionism. Perhaps you think Renoir is distinct, and sure, he is. Now what about the hundreds of non-famous artists that are not Renoir and are instead just trying to make novel art in exactly the style of Monet? You think their original works are illegal? You think they are more illegal than an ai generated monet painting that uses a different color palette to be distinct?

I'm not very interested in debating this further because I think we just disagree. I'm glad this is not the way copyright law actually works.

"Novel art" in exactly the style of Monet, is not entirely novel. I think it would be reasonable to allow Monet to have sole right to produce his style for 7 years or so, and then it enter the public domain. That rewards coming up with a new artistic style, which I feel is at least as valuable to reward as coming up with a new piece of artwork in an established style.

Again, my art history is weak, but when Picasso came up with his first cubist work, the cubism part of that work seems as valuable, and worthy of reward, as the actual instance of cubism that the work embodies?

There's a generally derivative style that follows the spirit of the age, and then there's a clearly copied style from a specific maker/creator/artist. It seems poor to protect the individual instance of an inspiring new style, but then not reward the creator of that style, not even with an acknowledgement.

FWIW, I'm not sold on either side of the argument. To me that's not how online discussion works. Also, I absolutely would not want copyright terms of the length we have to protect anything like this (nor anything really, they're obscenely long).

I would not of course want to inhibit the natural progression of styles, Monet's landscapes bore some similarity to JMW Turner, and a Chinese style called Lingnan, but this is a different thing to taking Monet's pallette used for water lilies, then painting a similar subject in the exact same style. If you do that immediately after Monet first presented his style for water lilies then I'd at minimum want you to say 'in the style of Monet' as a subtitle, and preferably have to pay him a little of your profit for the first few years.

Thanks for your interesting, thoughtful responses.