Recently, I have become fascinated with the notion of cycles. We humans tend to regard everything linearly, with a beginning and an end, because that is our individual experience. But taking a wider view, we can see that events tend to happen in cycles, that an end leads inexorably to another beginning. It’s easiest to see this in nature, with our regular seasonal cycles and the cycle of growth to death to fertilizer to new life again. In physics, the concept of eternal return posits that the universe has been recurring and will continue to recur in a self-similar form an infinite number of times. According to Eastern religions, we are all caught up in the Wheel of Life, an endless cycle of birth, death and rebirth, until we can escape via enlightenment.

Post-apocalyptic literature, a favorite of mine, is obsessed with endings, an interesting mind game in itself. What would happen if everything, as we know it, just stopped? But the concept of repeating patterns, of endless cycles, is even more of a mind bender. Recently, a couple of favorite TV shows have explored this theme.

**Spoilers for Battlestar Galactica and Lost follow, so stop reading now if you don’t want to know.**

Battlestar Galactica‘s controversial finale, seen as a happy ending by some and as a silly warning to be nice to your robots by others, was, in my view, highly pessimistic. Despite all their efforts to break the cycle of Cylon uprising and mutual destruction, even to the point of sacrificing their technological advantages, the surviving characters only managed to put the inevitable off for a few thousand years. But all this has happened before, and will happen again — and the cycle begins anew on modern-day Earth.

Lost is exploring similar themes, although it is not clear yet whether the pattern can actually be broken. Still, last night’s excellent season finale asks the question: If the pattern is destined to keep repeating, why take action at all? Why not just opt out? In my opinion, the show has not taken a side. We’ve seen characters opt out (Bernard and Rose), and they seem perfectly happy. We’ve seen other characters take action to try to change the pattern, break the cycle, but we don’t know if they will be successful. Even if they are unable to change the pattern, will just trying be enough for some kind of personal salvation or redemption? Is what matters making a choice and doing something, rather than the effects of that action? These are great questions to ponder on a sleepless night.

I am now getting interested in science fiction novels that explore similar themes. Here are a few that I could think of (ahoy, there may be spoilers ahead):

• Cloud Atlas by David Mitchell, which is structured in a cyclical manner progressing forward and then back through time.
• The Dark Tower series by Stephen King, in which Roland seems doomed to relive the events of his quest for the Dark Tower until he can find a way to break the cycle of repetition.
• The Mote in God’s Eye by Larry Niven and Jerry Pournelle, in which an alien civilization is doomed to cause its own apocalypse and then rise from the ashes over and over.
• Replay by Ken Grimwood, in which a man relives his life again and again (I haven’t read this).

Does anyone have other suggestions? I would love to hear them.