Popular children’s author Roald Dahl would have been 99 years old Sunday. Dahl was best known for his classic stories “Charlie and The Chocolate Factory” and “James and the Giant Peach,” creating imaginative worlds filled with vibrant characters. He also wrote “The Gremlins,” “Fantastic Fox,” “The Witches” and “Matilda.” During his career, Dahl wrote 19 children’s books.

Dahl married famous actress Patricia Neal and together they had five children. He died in 1990 in Oxford, England, at the age of 74. In celebration of the colorful author’s birthday, below is a list of Dahl’s most influential quotes, courtesy of Goodreads and BrainyQuote.

1. “And above all, watch with glittering eyes the whole world around you because the greatest secrets are always hidden in the most unlikely places. Those who don't believe in magic will never find it.”

2. “A person who has good thoughts cannot ever be ugly. You can have a wonky nose and a crooked mouth and a double chin and stick-out teeth, but if you have good thoughts they will shine out of your face like sunbeams and you will always look lovely.”

3. "I began to realize how important it was to be an enthusiast in life. He taught me that if you are interested in something, no matter what it is, go at it at full speed ahead. Embrace it with both arms, hug it, love it and above all become passionate about it. Lukewarm is no good. Hot is no good either. White hot and passionate is the only thing to be.” -- from “My Uncle Oswald”

4. “Somewhere inside all of us is the power to change the world.”

GettyImages-459922936 An annotated page from Roald Dahl's 'Charlie and the Chocolate Factory' by Quentin Blake is displayed at Sotheby's auction House on Dec. 4, 2014, in London. Photo: Getty Images

5. "It's impossible to make your eyes twinkle if you aren't feeling twinkly yourself."

6. “Two wrongs don't make a right.” -- from "The BFG"

7. “If you are going to get anywhere in life you have to read a lot of books.”

8. “When you're writing, it's rather like going on a very long walk."

9. "The writer walks out of his workroom in a daze. He wants a drink. He needs it."

10. "If my books can help children become readers, then I feel I have accomplished something important."