The Time Roads by Beth Bernobich

had taught mathematics at Éire’s largest university, in Awveline City. He was man of considerable reputation, their Aunt Eilín added, in a tone that suggested they would show respect for once.
    “What do you know about him?” Síomón asked Gwen.
    “Nothing,” Gwen replied, a little too quickly. Then, “Enough to know he’s worth listening to.”
    They had retreated to the attic above their bedrooms. Their aunt called it their schoolroom, but for Síomón and Gwen, it represented a refuge from the ordinary. Not even their most recent tutor, a man they both liked, ever ventured into this space. Síomón wanted to ask Gwen what she meant by worth listening to, but her expression had already closed. He took up the nearest book and pretended to study a diagram of numerical theory.
    Glasfryn arrived in midafternoon. Now stationed in the parlor, at their aunt’s command, Síomón and Gwen watched the liveried footman help the old man disembark from the carriage. He looked nothing like Síomón had imagined. Old, yes. But with a face so brown and seamed, it was as though he’d spent his years laboring in the sun, not confined to lecture halls. Gwen stood with her hands clasped together, silent and demure, but Síomón could tell she was studying Glasfryn as intently as he was.
    They took an early tea in the parlor while Aunt Eilín fussed over their guest, and Uncle Liam explained at tedious length about the twins’ schooling. Glasfryn stirred his tea and nibbled at the scones, but it was clear to Síomón that he was ignoring their uncle.
    “Let me talk to them,” he said, interrupting Aunt Eilín’s third inquiry about his health.
    Their aunt bit her lips, clearly irritated. Their uncle started to make excuses why he ought to remain present, but when Professor Glasfryn waved them away absently, Uncle Liam rose and motioned for Aunt Eilín to come with him.
    “But Liam,” she said softly. She glanced toward Gwen with an anxious expression, but then she shook her head and excused herself.
    Glasfryn waited until the door closed. “Now then,” he said. “Let us speak openly.”
    He began with straightforward questions about their lessons. They answered dutifully, just as they did with their tutors. Without their uncle to explain and repeat himself, the interview lasted only a quarter hour.
    Glasfryn fell silent and studied them a few moments through rheumy brown eyes. “What do you think about numbers?” he asked abruptly.
    Síomón and Gwen blinked. “What do you mean?” Síomón asked.
    “The ancient Greeks thought numbers were dead. Myself, I wonder if they were right. Maybe mathematics is like so much lumber. Take the sticks and build a house.”
    Gwen’s cheeks flushed pink. “What about Pythagoras?”
    “Answer my question first.”
    His tone was blunt, but Gwen smiled, unflustered. “If you view numbers as dead, then you imply a dead house, and one that invites termites. Besides, the premise is wrong.”
    Síomón caught his breath at her words, but Glasfryn’s mouth widened into a slow pleased smile. “How so, young miss?”
    “You assume a universal quality of men, just as your statement assumes a universal quality of mathematics, or even of numbers themselves.”
    “Does it follow, then, that you believe numbers exist apart from mathematics?”
    A slight hesitation. “I do.”
    Another pause, while Glasfryn drank down his cold tea. When he spoke again, it was to ask Gwen more questions. She answered—tersely at first, then with growing volubility. Glasfryn eventually turned his attention to Síomón and, in the same way, drew out more and more of what the twins had worked at in mathematics, their private research as well as their formal lessons.
    Questions soon gave way to discussion. With the professor leading, they spoke of topics ranging from the mundane to the bizarre—of the origins of mathematics, of whether numbers had undiscovered properties invisible to the ordinary mind, and the