Although I'm less than 100 pages in, I'm really enjoying David Leavitt's The Indian Clerk. Set in Cambridge, in the 1910s, one of its central characters, the mathematician G. H. Hardy, is a member of the Apostles - a secret society (which really existed, I believe Virginia Woolf's brother Thoby Stephen was a member) other members included Lytton Strachey, G. E. Moore, Rupert Brooke, John Maynard Keynes, and Bertrand Russell. Leavitt has a good time combining history and imagination in creating a meeting of the Apostles.
Here's an excerpt from earlier in the book when Hardy remembers first confronting one of the ultimate philosophical questions:
The Cranleigh vicar had taken him for a walk - at his mother's request, because he seemed not to be paying attention at church. It was foggy out; now he can imagine the gears shifting in the vicar's brain as he landed upon the idea of using the fog to explain faith. The fog, and something the boy would like. A kite.
"If you fly a kite in the fog, you cannot see the kite flying. Still, you feel the tug of the string."
"But in the fog," Harold said, "there is not wind. So how could you fly a kite?"
The vicar moved slightly ahead. In the humid stillness, his torso blurred and wavered like a ghost's. It was true, there was not a touch of wind.
"I use an analogy," he said. "You are, I trust, familiar with the concept."
Harold did not answer. He hoped the vicare would mistake his silence for pious contemplation, when in fact the young man had just eradicated any last shred of faith that the boy held. For the facts of nature could not be denied. In fog there was no wind. No kite could fly.
They returned to his house. His sister, Gertrude, was sitting in the drawing room, practicing reading. She had only had the glass eye a month.
Mrs. Hardy made tea for the vicar, who was perhaps twenty-five, with black hair and thin fingers. "As I have been trying to explain to your son," the vicar said, "belief must be cultivated as tenaciously as any science. We must not allow ourselves to be reasoned out of it. Nature is part of God's miracle, and when we explore her domain, it must be with the intention of better comprehending His glory."
"Harold is very good at mathematics," his mother said. "At three he could already write figures into the millions."
"To calculate the magnitude of God's glory, or the intensity of hell's agonies, one must write out figures far larger than that."
"How large?" Harold asked.
"Larger than you could work out in a million lifetimes."
"That's not very large, mathematically speaking," Harold said. "Nothing's very large, when you consider infinity."
The vicar helped himself to some cake. Despite his emaciated figure, he ate with relish, making Mrs. Hardy wonder if he had a tapeworm.
"Your child is gifted," he said, once he had swallowed. "He is also impudent." Then he turned to Harold and said, "God is infinity."
Marvelous- characters are clearly drawn through well chosen details, we are shown, not told, and there is a pall of humor cast over the scene coming from the retrospective point-of-view from which it was written. Maybe it's just the time period and setting, but the book is evoking E. M. Forster for me.