Back when I was first learning about him, I was stunned to discover that the songs in some of his early shows like Company (1970) were originally viewed by some critics as ‘cold.’ To me his music seems the opposite of cold; his melodies have always seemed warm and inviting, while his harmonies have invariably stuck with me. I know nothing about music theory, but I do know that great composers use certain chords and rhythms and harmonies to evoke sadness or joy or melancholy. I suspect that if Mr. Sondheim were to write a book about his music, rather than his lyrics, he would explain just as clinically how he creates mood with harmony.

But reading Finishing the Hat made me realize that my assumption had been way too blithe; it was a way of letting myself off the hook. What I had long admired about Mr. Sondheim’s lyrics — what everyone admires, really — was their sheer gleaming intelligence. But what I had been missing — and what I could see, at last, on the page, as I listened to his songs — was their wealth of emotion, and how often they directly spoke to me.