All of Andrei Tarkovsky's films briefly were (and most still are) available free online. Seems like a good time to watch one of them. Especially since Akira Kurosawa has said that "Every cut from his films is a marvelous image in itself," which could be said of Kurosawa's films too. I started with Solaris, since that was already in my Roku queue.
As Kurosawa implies, it's a very stylish film. No diagonal zippers but bondage trousers and leather jackets, and in 1972 (i.e. five years before clothes like that became fashionable). It's obviously been influential in other ways, too, most obviously on Moon, which is also (but not nearly as) good.
It's probably the most philosophical film I've ever seen, with themes from Kant, Heidegger, and Wittgenstein. Where is the border between experience (of reality) and hallucination? What does it take, or mean, to be human? If a sea or planet could communicate, would we understand it? What obligation do we have to be human (e.g. rational)? If I remember rightly, the questions "What do you mean, 'how'?" and "What do you mean, 'why'?" are both asked directly (i.e in the dialogue, by characters in the film). These are interesting questions. What, when, who, and where can all be answered by giving the name of some thing, time, person, or place. But how is usually (always?) answered "Like this," so it requires the ability to copy, to do something similar but not actually the same. If you paint a bit of wall to show me how it's done, I shouldn't then paint the same bit of wall or repeat your words of instruction, for instance. I should do what is relevantly the same. So the meaning of 'how' gets at something about rule-following, the nature of human being, etc. The same with 'why,' which also involves issues of relevance, importance, responsibility, etc.
Why is there no Solaris and Philosophy book? There is Solaris, of course, which I'll have to read.