I just had a thought about Back to The Future [parts II and III].
One of the common idioms of the film is that the protagonist, Marty McFly has a (seemingly genetic) trait of foolish bravery whenever anyone calls him a “Chicken” (for anyone reading this in a lack of cultural context, ‘chicken’ is a reference to cowardice, just like ‘yellow’ [it will probably be forgotten in history, such specificities of idiolect…]). We find that this goading of being called a chicken affects Marty’s relatives throughout time; his ancestor from 100 years previous; his father, his future son, and even his future self. I think one of the ultimate morals of the whole three series of films is that at the end, Marty learns to overcome this weakenss, which has always gotten him, and his family into trouble; and in that way, improved himself, and possibly his future and genetic line. This is a moral of the story, in the most obvious sense.
Of course, there are a lot of interesting epistemic and metaphysical issues with the whole time travel thing; but I’ll leave that to the philosophers of physics for now. There seems to be a very human platitude, that; even in a world with time travel, the future is not fixed, and we can change ourselves for the better.
I should stop listening to Huey Lewis and the News; making me think this rubbish sophism….