He felt himself suddenly reeling back to Harvard, standing in front of his “Symbolism in Art” class, writing his favorite number on the chalkboard. 1.618. Langdon turned to face his sea of eager students. “Who can tell me what this number is?” A long-legged math major in back raised his hand. “That’s the number PHI.” He pronounced it fee. “Nice job, Stettner,” Langdon said. “PHI’s ubiquity2 in nature, clearly exceeds coincidence, and so the ancients assumed the number PHI must have been preordained3 by the Creator of the universe. Early scientists heralded one-point-six-one-eight as the Divine Proportion.”
“Hold on,” said a young woman in the front row. “I’m a bio major and I’ve never seen this Divine Proportion in nature.” “No?” Langdon grinned. “Ever study the relationship between females and males in a honeybee4 community?” “Sure. The female bees always outnumber the male bees.” “Correct. And did you know that if you divide the number of female bees by the number of male bees in any beehive in the world, you always get the same number?” “You do?” “Yup. PHI.” The girl gaped. “NO WAY!”
“Way!” Langdon fired back, he began racing through slides now—spiraled pinecone petals, leaf arrangement on plant stalks, insect segmentation—all displaying astonishing obedience to the Divine Proportion. “This is amazing!” someone cried out. “Yeah,” someone else said, “but what does it have to do with art?” “Aha!” Langdon said. “Glad you asked.” He pulled up another slide—Leonardo da Vinci’s famous male nude-The Vitruvian Man. “Nobody understood better than Da Vinci the divine structure of the human body. He was the first to show that the human body is literally made of building blocks whose proportional5 ratios always equal PHI.” Everyone in class gave him a dubious6 look.
“Don’t believe me?” Langdon challenged. “Next time you’re in the shower, take a tape measure.” A couple of football players snickered. “All of you. Guys and girls. Try it. Measure the distance from the tip of your head to the floor. Then divide that by the distance from your belly button to the floor. Guess what number you get.” “Not PHI!” one of the jocks blurted7 out in disbelief. “Yes, PHI,” Langdon replied. “One-point-six-one-eight. Want another example? Measure the distance from your shoulder to your fingertips, and then divide it by the distance from your elbow to your fingertips. PHI again. Another? Hip to floor divided by knee to floor. PHI again. Finger joints. Toes. Spinal8 divisions. PHI. PHI. PHI. My friends, each of you is a walking tribute to the Divine Proportion.” Even in the darkness, Langdon could see they were all astounded9. He felt a familiar warmth inside. This is why he taught.
“Come on,” Sophie whispered. “What’s wrong? We’re almost there. Hurry!” Langdon glanced up, feeling himself emerge from a schooling thought. He realized he was standing at a dead stop on the stairs, paralyzed by sudden revelation10.
O, Draconian devil! Oh, lame saint!
Sophie was looking back at him. It can’t be that simple, Langdon thought. But he knew of course that it was. There in the bowels of the Louvre...with images of PHI and Da Vinci swirling through his mind, Robert Langdon suddenly and unexpectedly deciphered11 Saunière’s code. “Fibonacci numbers only have meaning in their proper order. Otherwise they’re mathematical gibberish12.”
Sophie had no idea what he was talking about. She plunged13 her hand into her pocket and pulled out the photograph, studying her grandfather’s message again.
13-3-2-21-1-1-8-5
O, Draconian devil!
Oh, lame saint!
What about the numbers?
Without another word, Langdon pulled a pen from his jacket pocket and rearranged the letters in each line.
O, Draconian devil! Oh, lame saint!
was a perfect anagram of...
Leonardo Da Vinci! The Mona Lisa!
兰登深感诧异：“你祖父教过你PHI值？”“当然，黄金分割。”她的表情变得害羞起来，“其实，他过去常开玩笑说我有一半符合黄金分割……那是因为我名字里的字母。”兰登想了片刻，然后嘀咕：so-PHI-e.
他忽然产生了一种幻觉，仿佛自己又回到了哈佛，站在教室前面讲解“艺术中的象征”,在黑板上写下他最喜爱的数字：1.618。兰登转向台下众多求知若渴的学生：“谁能告诉我这是个什么数字？”一个坐在后排的数学系长腿学生举起手：“那是PHI值。”他把它读做“fee”。“答得好，斯提勒。”兰登说，“PHI在自然界中无处不在，这显然不是巧合，所以祖先们估计PHI值是宇宙的造物主事先定下的。早期的科学家宣布1.618为黄金分割。”
“等一下，”一名坐在前排的女生说，“我是生物专业的学生，我从来没有在自然界中见到黄金分割。”“没有吗？” 兰登咧嘴笑了，“研究过一个蜂群中的雌蜂和雄蜂的关系吗？”“当然。雌蜂总是比雄蜂多。”“对。你知道吗？如果你将世界上任何一个蜂巢里的雌蜂数除以雄蜂数，你永远得到一个相同的数值。”“真的吗？”“是的，就是PHI。”女生目瞪口呆。“这不可能。”
“可能！”兰登反驳道。他开始快速地播放幻灯片——螺旋形的松果花瓣、植物茎上叶子的排列、昆虫身上的分节——所有这些竟然都符合黄金分割。“真不可思议！”有人大叫。“不错，可这和艺术有什么关系呢？”另外一个人说。“啊！问得好。”兰登说着，放出另一张幻灯片——列昂纳多·达·芬奇的著名男性裸体画《维特鲁威人》。“没有人比达·芬奇更了解人体的奇妙结构，他第一个宣称人体是由完全符合黄金分割比值的‘模块’组成。”在座的人都向兰登投来怀疑的目光。
“不相信？”兰登反驳，“下次你们洗澡的时候，带上一根卷尺。”几个橄榄球队的学生窃笑起来。“你们所有人，男生和女生，试试看。测量一下你们的身高，再用身高除以你们肚脐到地面的距离。猜一猜结果是多少。”“不会是PHI吧！”一名体育生用怀疑的口吻脱口而出。“就是PHI，”兰登回答道。“1.618。想再看一个例子吗？量一下你肩膀到指尖的距离，然后用它除以肘关节到指尖的距离，又得到了PHI。再看另一个例子，用臀部到地面的距离除以膝盖到地面的距离，又可以得到PHI。手指关节、脚趾、脊柱的分节，你都可以从中得到PHI。朋友们，你们每个人都充分说明了黄金分割。”即使在黑暗中，兰登可以看出大家都很震惊。一股熟悉的暖流涌上他的心头，这正是他教学的原因。
“快点，”索菲小声说。“怎么了？我们快到了。快一点！”兰登抬起头，觉得自己从学校记忆中回到了现实。他发现自己在楼梯蓦地定住，被突然的发现惊呆了。
啊，严酷的魔王！噢，瘸腿的圣徒！
索菲回头望着兰登。不可能这么简单，兰登想。但他肯定应该是那样。置身于卢浮宫深处，脑海中盘恒着PHI和达·芬奇的画面，罗伯特·兰登忽然出乎意料地破解了索尼埃的密码。“斐波那契数字只有按顺序排列才有意义，否则他们在数学上就是杂乱无章的。”
索菲不解其意。她伸手从口袋中掏出照片，再次研究起祖父的留言：
13-3-2-21-1-1-8-5
啊，严酷的魔王！噢，瘸腿的圣徒！
这些数字怎么了？
兰登不再多言，从夹克衫的口袋中掏出一支钢笔，将每行的字母重新排列来：
O，Draconian devil！(啊，严酷的魔王！)
Oh，lame saint！(噢，瘸腿的圣徒！)
恰好可以被一字不差地拼成：
Leonardo Da Vinci！(列昂纳多·达·芬奇！)
The Mona Lisa！(蒙娜丽莎！)
