I have long held that Lewis Carroll's Alice in Wonderland is my all time favorite children's book, and I still believe. But Through the Looking Glass is the sequel and almost equivalent in how much I like it. It has totally different strengths and appeals, but they both demonstrate a love of language, fantasy, science, and mathematics held by their author. I know that many people eschew the whole idea of Alice in Wonderland because of the unfounded association of that with the drug culture, but the same cannot be accused of Through the Looking Glass.
It is a fanciful but mathematical stroll through a game of chess, and many quotes and characters have become famous in our society based on it. Lewis Carroll's ease and comfort with philosophy, mathematics, and LANGUAGE are truly encompassed in the work, and it's a lot of fun! I continue to love and respect the works of Lewis Carroll, despite the fact that he has been dead for years and years.