The ancient Greeks had a word for loving Sophia — philosophy. This book takes the simpler route and just puts her on the cover.

Wisdom, empresses and a name the whole world agreed on

Sophia is the ancient Greek word for wisdom — not a name that later acquired a meaning, but a meaning that became a name. When the Greeks coined philosophia, "love of wisdom", they built it from the same word. The most famous Sophia in the world isn't a person at all: Hagia Sophia in Istanbul is dedicated to Holy Wisdom itself, and for centuries the name travelled through Byzantine princesses and Russian regents before arriving in western Europe. One of them mattered enormously to Britain: Sophia of Hanover, whose descendants — and only hers — have held the British throne since 1714.

For most of the twentieth century Sophia was a quiet classic in English, the name of grandmothers and of Sophia Loren. Then it rose like almost no other name has: it reached number one for girls in the United States in 2011 and held the top spot for three years running. What makes it genuinely unusual is how far the agreement stretches — in its Sophia and Sofia spellings it has topped or crowded the charts in Italy, Spain, Mexico, Germany and half a dozen other countries at the same time. Very few names are a favorite on several continents at once; this is one of them.

That global reach is a quietly practical gift. A girl named Sophia can travel almost anywhere in the world and find her name pronounced with ease — three open syllables that Italian, Spanish, German and English speakers all say without hesitation, each convinced the name is theirs. Not many children grow up with a name that needs no translation; a Sophia does, and a story written for her gets to use every syllable of it.

What Sophia gets called at home

• Sophie — The everyday form, and a name with its own long history — in France and Britain, Sophie has stood on its own for centuries. If your Sophia mostly hears this at home, the story can use it in every line of dialogue while the cover keeps the full name.
• Soph — The clipped form that tends to arrive with the school years, usually from friends first. It sounds casual and grown-up at the same time — the version shouted across a playground, and later the one that survives into text messages.
• Fia — The rarer pet form that keeps the ending instead of the beginning. Families who use it usually like that it belongs to their Sophia alone — hardly anyone else's — and that it works as a secret family word as much as a nickname.
• Fifi — The toddler-era nickname, often self-invented when Sophia is still learning to pronounce her own three syllables. It rarely survives to school age, which is exactly why parents remember it fondly.