Cracked vessels. That is what Professor Cornel West says we are.
West is one of my favourite philosophers. He is brave and exuberant and generous of heart. He concerns himself with our shared humanity, the ties that bind us and the things that keep us apart.
He is fluent and adept at getting his views across; he goes on TV a lot.
Some of his detractors scorn him for that - they say he's more interested in self promotion than the purity of philosophical thought - but I enjoy seeing West talking about the Socratic imperative on late-night talk shows; I like it that he puts it about.
In the last chapter of his autobiography, Brother West, the philosopher considers his own mistakes, the failed marriages, the money troubles, the bad press, and concludes that he's just a cracked vessel like anyone else.
A cracked vessel "trying to keep it funky", he says. I'm not sure I know how to keep it funky. I can't dance, but I think keeping it funky means keeping it real, and keeping it real means remembering that we are vessels, and in every vessel, however ornate, there are cracks. Taken as a whole, our cracks are myriad, of course.
Impatience, intolerance, bitchiness, an inability to keep it in one's pants. Pride, greed, cruelty, gluttony, lust for power. All the big stuff, all the juicy stuff, the stuff that looks meaty written down.
These base instincts are not only a part of our humanity, they define it. So goes the cliche. For those who make sense of life through stories, they are an invaluable component of the narrative, the decision (or otherwise) to act on a selfish motive is a reliable fulcrum for just about any plot.
Certainly, the Greeks knew this. The Classical tradition of hubris was there even before the Christians came up with original sin. We are human, then, and as such we are cracked vessels - we possess hubris, we make mistakes.
So say West, Shakespeare and the Greeks. Which brings us, naturally, to Charlie Sheen.
Sheen, a funny man, handsome once. Until recently, the highest-paid actor on TV. Sheen says he's winning, chalking up runs in his underwear, kicking it across the board. And certainly the spectacle of Sheen calling out his producers on camera - savaging the cynical hands that feed him so publicly, so fearlessly, so absolutely stark-raving, straws-in-your-hair crazily - was one to behold. It's not every day you get to see the richest actor on television going rogue in the exact medium he commands.
For sheer entertainment value that was hard to beat; certainly it provided us all with some post-earthquake light relief. There is a problem though, with Sheen's latest show.
For viewers of any momentous spectacle the thrill is in the moment of realisation, when you grasp what is before you, when the full import of it knocks you flat.
For me that was in the first 20 seconds of watching Sheen's first television interview last weekend - making sense of the wizened features, the warlock talk, the oddly shrunken skull.
As these elements coalesced into one image, I realised the full import of what I was seeing - I was party to a crackhead in full flight.
I confess I was thrilled. This does not reflect well on me.
It was a nasty, voyeuristic kind of thrill. Peeping at a drug addict; a new televisual low. I've seen crackheads before, obviously, but I've never seen a famous one. Well, not one who's been on Two and a Half Men.
So Sheen talked, and I listened. And such talk! Warlocks, goddesses, Vatican assassins, strafing runs.
It was as though he'd spent the last few weeks holed up somewhere playing Dungeons and Dragons on meth. It was enthralling, poetic, completely mad.
I watched a few of those videos but after a while I couldn't watch anymore. I felt a bit sick, to be honest. As fluent as he comes across, the man is clearly as addled as they come. Past some point after which the brain chemistry is sadly rearranged.
His ravings have been linked to the world over but he's still as twitchy and wall-eyed as any addict you'll meet, with the same litany of trouble and failures that follow an addict around. Rich and famous he may be, Sheen is a man who has attacked women.
He is a father whose young children have been taken away from him, an addict spiralling down.
Besides hubris, pity and terror is the only thing I remember from studying the Greek tragedians. The Aristotelian idea that for drama to effect catharsis, it must produce pity and terror.
Sheen is an odd sort of vessel for catharsis, plenty cracked though he may be, but it is through him that we are purging our own emotions - pity for him, maybe; for ourselves, definitely.
It is impossible to watch the disintegration of another human being without feeling the terror of what we may become. "Alas, poor Sheen, we knew him." He's our 21st-century viral version of Yorick's shrivelled skull.By Noelle McCarthy Email Noelle