Salvador Dali did a painting entitled "The Persistence of Memory"; it's one of his works featuring a dripping clock. How tiresome such clocks become; how tiresome, perhaps, Dali became. Memory is the same as regret, sometimes, and it is regret I find most persistent and daunting.
This is a significant confession for one who struggles to be a stoic, since regret may be said to be a feeling that results from ascribing significance to something clearly beyond our control, as it is a feeling evoked by memory or the consideration of something in the past. We regret something done or not done, something that cannot be undone or done now. It is an exercise in futility in and of itself. In stoicism there is probably no purer example of something we should treat as indifferent in the ancient sense.
But we (or at least I) do not treat it as indifferent. I dwell on certain things of the past, sometimes of the distant past; they pop up now and then in dreams, or even in waking life when memory speaks to me too loudly. Memory may be quashed when one is awake, or overwhelmed by present concerns, but dreams present a real difficulty. Some of us can alter our dreams as they take place; I have been able to do this, sometimes. But I can't when the dream involves someone or something that is the subject of my regrets, since in such dreams I find my dream-self acting to prevent what I regret from taking place or to explain my regret and express how persistent it is.
But the expression of regret seems to degenerate into cloying cliche all too rapidly. What indeed can be said in explanation; what can be said to acknowledge the pain of regret that doesn't make one sound like a Romantic poet at his worst? If one can't overcome regret one can at least avoid histrionics.
If the regret is strong, though, it is not entirely a matter of indifference as it effects how we feel think and act now, which are things within our control. We can correct ourselves as far as the present is concerned, and in this sense regret may be useful, I suppose.
Perhaps there is a kind of wisdom behind the sacrament of penance. It may be a means to assuage regret. We regret, we confess our wrongdoing, we are forgiven. But penance involves a most specific kind of regret and remorse, and the regret is such that it persists in a different way entirely. We regret doing something which displeases an eternal being, always there to forgive and available for reconciliation. The prodigal son's everlasting father. When our regret involves someone dead, or a love lost, there can be no reconciliation; there can be no renewal of love, as nothing can be the same. What could have been is gone and can't be recovered.
Blood or water under the bridge, we say, and so the past is no matter how much we cherish it or how much it is a source of pain and remorse. But perhaps there is more than memory involved. Possibly we still want now what we could have had then. Regret can be present desire for something which could have been in the past but is not now and cannot be now. This is piling futility on futility. Do we confabulate when we experience regret?
Is regret merely a persistent dream or fantasy, or the recognition that a dream or fantasy which could have been was lost to us and we have only ourselves to blame?
We are disturbed not by things but by our view of them, to paraphrase the wise Epictetus. So I am disturbed not by the past but what I think of the past, and perhaps what I superimpose on the past--what I imagine the present would be and the more recent past would have been.
I certainly regret, and that should be all. I can feel regret, I can express regret, and have done so. What I failed to do I can't do now. The regret is of the past and is itself a part of the past, and should play no more part in the life left to live.