The Cat in the Hat (film) start until after the 2000 Christmas/comedy film "How the Grinch Stole Christmas", based on another Dr. Seuss book of the same name, became a commercial success. Brian Grazer, who was the producer of "The Grinch", stated, "Because we grew up with these books, and because they have such universal themes and the illustrations ignite such fantasy in your mind as a child — the aggregation of all those feelings — it leaves an indelible, positive memory. And so when I realized I had a chance to convert first "The Grinch" and then, "The Cat in the Hat", into movies, I
The Cat in the Hat read, and Spaulding provided Geisel with a similar list. Geisel later told biographers Judith and Neil Morgan that Spaulding had supplied him with a list of 348 words that every six-year-old should know and insisted that the book's vocabulary be limited to 225 words. However, according to Philip Nel, Geisel gave varying numbers in interviews from 1964 to 1969. He variously claimed that he could use between 200 and 250 words from a list of between 300 and 400; the finished book contains 236 different words. Geisel gave varying accounts of how he conceived of "The Cat in the Hat".