"But a moral system based on the will of God has enforcement built into it. What motivation do people have for doing the morally right thing? If they don't, they will be displeasing God, and there will be, as we say, hell to pay.

"Cass Seltzer is an atheist with a soul, who feels sympathy for all sentient beings and thinks that others ought to, too. Lovely sentiments. But what if they don't feel as he feels, and what if they don't want to? What means does he have of compelling them to do the right thing?

"For him there's no immortality. Death is the end, and everyone ends up exactly the same. It doesn't make any difference whether you live as a Hitler or a Mother Teresa. There's no relationship between the moral quality of your life and your ultimate fate. Death is final, over and out, and, given its finality, what reason could there be for consistently living the moral life rather than living only for one's self?

"My last question to you, Professor Seltzer, is, what motivation for adopting the moral point of view can you possibly offer without a belief in God and immortality?"

Fidley's tone of belligerent confidence has returned with this last speechifying question. The line about a morality with muscle is, clearly, something he really believes. Roz is sitting on the edge of her seat- literally, as she would say-and her hands are clasped in front of her almost in supplication, and he can't help smiling at the sight of her. She's a good friend, but she's also distracting him.

"Professor Fidley worries that, without a belief in God, people will act only for reasons of self-interest instead of behaving morally. But then what does he offer as the only persuasion to adopt the moral point of view? Concern for one's self, in this life and the next. Without this, he says, there's no reason to act morally. In the end, it's Professor Fidley who reduces morality to self-interest.

"And it's no wonder that in the end he has to fall back on self-interest as the ultimate motivation for morality. He can't see what can be morally compelling about morality, in and of itself. If he did see that, he wouldn't think that he needs God to magically inject the morality into morality. And since, according to him, there's nothing compelling about morality in itself, he also thinks morality requires some lash to punish us in an afterlife if we don't comply. So, in the end, all that he can appeal to are motivations of self-interest. In the end, all that he can offer people as a reason to act morally is for them to act in their self-interest, currying favor with an authority that can dole out rewards and mete out punishments.

"But if the moral point of view is something that we humans can, with a great deal of effort, reason our way into, then morality itself provides the motivation to be moral. The reason to do the moral thing is that it's the moral thing to do; to do anything else is to make a shambles of our thinking, of our values, of our mattering. Our seeing for ourselves why it's the moral thing to do is what compels us.

"When we're trying to teach a child why it's wrong to pick on another child, do we say, 'It's wrong because if I catch you doing it again you'll be spanked,' or do we, rather, say, 'How would you feel if someone did that to you?' And when we're wrestling with our own conscience, trying to resist a temptation we know is wrong, do we think to ourselves, 'If I do it, then I'll be flambeed in hell's fires,' or do we think, 'Would I want everyone in the world to behave this way? Wouldn't I feel moral outrage if I learned of someone else doing this?'

"There is a point of view that's available to all of us. The philosopher Thomas Nagel called it the 'View from Nowhere.' It's the source of so much of our philosophical reasoning, including our moral reasoning. When you view the fact that you happen to be the particular person that you are from the vantage point of the View from Nowhere, that fact shrivels into insignificance. Of course, we don't live our life from the perspective of the View from Nowhere. We live inside our lives, where it's impossible not to feel one's self to matter. But, still, that View from Nowhere is always available to us, reminding us that there's nothing inherently special or uniquely deserving about any of us, that it's just an accident that one happens to be who one happens to be. And the consequence of these reflections is this: if we can't live coherently without believing ourselves to matter, then we can't live coherently without extending that same mattering to everyone else.

"The work of ethics is the work of getting one's self to this vantage point and keeping it relevant to how one sees the world and acts. There are truths to discover in that process, and they're the truths that make us change our behavior. To assert that there has been no cumulative progress in discovering moral truths is as grossly false as to say there's been no cumulative progress made in science. We've discovered that slavery is wrong, we've discovered that burning heretics in autos-da-fe is wrong, we've discovered that depriving people of rights on the basis of race or religion is wrong, we've discovered that the legal ownership of women is wrong.

"Religious impulses and emotions are varied. There are expansive, life-affirming emotions that can find a natural expression in the context of religion, which is why I can never offer a wholesale condemnation of religion, even though Professor Fidley seems to think I do. But when religion encourages what I can only describe as a moral childishness that blocks the development of true moral thinking, then I do condemn it. When religion tells us that there is nothing more we can say about morality than that we can't see the reasons for it, but do it if you know what's good for you, then I do condemn it. We can do better than that. We can become moral grown-ups. And if there were a God, surely he would approve."

Cass stops speaking, not because he has found the perfect parting shot, but because he is spent. His opening statement had been shorter than Fidley's by half, so he had felt it only fair to help himself to as much time as he wanted at the end, when the words just kept coming. There's a silence for several long moments, an uncanny silence considering how many people are crowding Memorial Church, and Cass wonders whether he went on too long and too emotionally, and whether he has embarrassed himself and everyone here. Then the hall erupts. Lenny stands at the lectern beside Cass, waiting for the applause to die down so he can say the few words that he's been saving for the end, including the best of the agnostic jokes. But he doesn't get the chance, because when the applause dies down the crowd surges forward, and Cass is surrounded.

XXXV.

The Argument from Solemn Emotions It's only when Cass is settling himself into his car that he realizes that he's euphoric. He hasn't had the time to observe the state of his mind, or maybe the euphoria has descended on him right at this moment. I'm drunk, he thinks, pushing the Start button of his Prius and silently steering onto Massachusetts Avenue.

William James, cataloguing the varieties of rapture that can seize hold of a person, hadn't scorned to include intoxication: "Sobriety diminishes, discriminates, and says no; drunkenness expands, unites, and says yes. It is in fact the great exciter of the Yes function in man. It brings its votary from the chill periphery of things to the radiant core. It makes him for the moment one with truth."

Yes, Cass thinks, making a left onto Bow Street, driving past the Harvard river dorms. He feels as if he hardly has a need to breathe, as if he's holding his breath as the Yes function is pumping, and that for as long as he can sustain this breathless Yes he is in perfect harmony with the world, no matter the wildness and pang of life. All the irreconcilabilities are melded sweetly together, the pulling-apartness that shreds the human heart is stilled in the yesness that's resounding, and all manner of things shall be well.

My soul is blotto, he says, and laughs out loud, and William James himself would approve. Straight ahead of him, Weeks Bridge is spectrally glowing, the wide white steps leading into a self-enclosed space of solemn emotions, and he gazes lovingly at it as he makes a right onto Memorial Drive.

The traffic light on the corner of Memorial Drive and JFK, which is always red, is green for him, and as he turns left and glides over the river, he glances left to get another glimpse of the mystical radiance of Weeks Bridge, and it induces a surge of love that would be more appropriate if directed toward a person than a brickwork structure. He turns left onto Storrow Drive and gets another loving look at the bridge and at the redbrick and pristine jewel-colored domes and spires of the Harvard skyline, the architecture that had impressed him twenty years ago with the insistence of its purity and American authenticity, and his love for it, too, is inappropriately tender.

As he makes the right that will take him to the turnpike, he realizes that the reason these loves feel as if they're directed toward a person is that they are. All are expressions of his love for Lucinda. It's Lucinda who has reset the vector of his life, giving a vigorous spin to the wheel of his fortune. No wonder his soul is intoxicated-shit-faced, as Mona might put it and he loves Mona again, now, too, mindful Mona, front and center-and he laughs as he exits for Logan Airport, and then parks the car in the short-term lot.

He's twenty minutes late and his Yes function is still pumping at capacity, and the sound of it is laughter. He laughs when he checks the American Airlines monitor and learns that her plane is only now landing, and he laughs when he remembers that she had had to check her luggage, since she had taken her running and swimming clothes and the creams she has for every body part; and again he laughs when he sees that Carousel D is labeled "AA 211, Dallas," which is the flight she was on, and then the carousel starts to spin and he recognizes the first suitcase to emerge and rushes to retrieve it, but another hand deftly lifts it before he makes contact, and it's hers.

"Lucinda!"

She looks up at him, startled.

"Cass?"

"Lucinda!"

"Wow, you did come."

"Of course! I said I would."

She smiles, and again there's that slight tremor in her vermilion bow that softens the hardness that sometimes settles over it.

"I'm glad you're here," she says simply, and she kisses him sweetly, and it doesn't surprise him, and he relieves her of the green leather bag with the monogram "LM," and they walk together toward the terminal exit.

"I'm tired," she says.

"Of course you are. If you want to wait here, I'll get the car and bring it round."

"No, I want to walk. It's the staying still that's wearying."

They settle into the car, and she leans back and closes her eyes, and the solemn joy he feels is the solemn joy that William James describes.

"Anything happen while I was gone?" she asks.

A solemn joy, James had written, preserves a sort of bitter in its sweetness. A solemn sorrow is one to which we intimately consent.

"Well, I'm coming straight from the debate at Harvard."

"Debate?"

"With Fidley."

"Ah yes, Felix. You know that he and I published a paper together?"

"'Mandelbaum Equilibria in Hostile Takeovers.'"

"Right! You fang him good?"

"I don't know whether it would be what you would call good fanging. I think it was a good debate."

"Well, who won?"

"I kind of think I did."

"Kind of?"

"Afterward, Luke Nanovitch said, 'Score one for our side.'"

"Luke Nanovitch was there?"

"Yes. A lot of Auerbach's cartel were there. He must have ordered them to attend. Arthur Silver and Nicholas Duffy and Eliza Wandel and Marty Huffer."

"Sounds like quite the event. Those are brand names."

"There was only one brand name I wanted there. Lucinda Mandelbaum."

She opens her eyes and looks sideways at Cass and smiles and then closes her eyes again and leans back.

"The debate is going up on my agent's Web site, if you want to watch it. There were over a thousand people there. If I had had any idea, I would have been too terrified to show up."

"My talk for Pappa is posted on the Internet, too, if you want to watch it."

"Of course I want to watch it! The question is, will I understand it?"

"Maybe not all the technical points, but the general ideas, sure."

"Is it related to the Mandelbaum Equilibrium?"

"Only tangentially. It's related to regret."

"Regret, as in wishing you could change the past?"

"Exactly. Regret is a form of counterfactual thinking, and it can be modeled in game theory. People measure how well their strategy was not only by what they win, but by what they could have won. I developed some mathematics that puts regret into the equations."

"The mathematics of regret. It sounds hopeful."

"Yes," she says and smiles again, "it's very hopeful," and the silence in the car is charged with their intimacy and the sweet naturalness they've easily found their way back into.

"Something else happened while you were away."

She opens her eyes and looks at him.

"What?"

"I want to show you when we get home. I've been looking forward all week to showing you."

She smiles and leans back again.

"Oh, then, it's something good."

"Yes, very good."

"I'd thought for a moment it was something bad."

"Bad? Why?"

"Your voice sounded ominous."

"Ominous?"

"Well, solemn. I thought maybe some long-lost love of yours had shown up on our doorstep."

"Well, that, too," he says, and they both laugh.

They've exited onto Storrow Drive now, and there's Weeks Bridge rising up before them, and Cass says, "The first night you were gone, I couldn't sleep, and I finally just went for a walk at four a.m., and I found myself on Weeks Bridge," and he points right and her eyes follow where he's pointing. "The river was frozen except where it flowed through the three arches. It looked as if a cathedral had been carved into the ice."

"Has it melted now?"

"Yes."

"Too bad. It sounds sublime."

"That's exactly the right word. That's the word I had thought at the time. Sublime."

She smiles again, and they cross back over Larz Andersen Bridge and through Harvard Square, and Cass is contemplating how irresistible that drunken sense is that makes you feel that you and the world are in silent cahoots.

"Was Fidley fierce?"

"Pretty fierce."

"Yes, I imagine he'd be a tough antagonist."

"Before I even walked into the place, he was intimidating the poor Agnostic Chaplain of Harvard."

She opens her eyes.

"Did you say the Agnostic Chaplain of Harvard?"

"I did. It was the Agnostic Chaplaincy that sponsored the debate."

"How droll!"

"Yes," he says, laughing, "it is droll!"

"I guess I'll never understand the religious mind."

"What about the agnostic mind?"

"No, not that one either."

They drive down Massachusetts Avenue and turn onto Upland Road, and he pulls into the driveway, and the light from the streetlamp falls lavishly on them both.

"You look so tired I feel I should carry you in."

She smiles. "I feel so tired I might let you."

He gets her suitcase out of the backseat and shoulders her computer bag and her purse, and they go through their gate and up the porch stairs, and he unlocks the door, and they climb the narrow stairs to their first floor side by side.