Like our planet, the planet in Tarkovsky's Solaris thinks. But its thoughts are produced by a sea that covers its surface, instead of primates with large brains. The sea's thinking affects human thinking. It acts on the human brain in much the same way a hallucinogen acts on neural receptors. The astronauts begin seeing the dead, seeing women floating above their beds. Solaris is science fiction in the condition of music. (Northwest Film Forum, 1515 12th Ave, 267-5380. 6 and 9:15 pm, $5—$8.50.)