Quite a lot of our contemporary culture is actually shot through with a resentment of limits and the passage of time, anger at what we can't do, fear or even disgust at growing old. ↗
Freedom Summer, the massive voter education project in Mississippi, was 1964. I graduated from high school in 1965. So becoming active was almost a rite of passage. ↗
The passage of time is a continuing thing. At 18, you're going to live forever, and you are definitely not at 52, so that is a recurring topic. I still think it's the main stuff. ↗