There have been many science-fiction novels written about time travel, but The Door into Summer is my pick for the greatest among them. It comes remarkably close to conveying the very theory of the subject in layman's terms.

I'm not saying Heinlein's arguments are correct, but they darn near make sense. The experiment with the two coins and two guinea pigs (just one, actually) is fascinating, and Heinlein's introduction of several paradoxes in the protagonist's actual temporal dislocation lends his science even more believability.

Time travel doesn't even enter into the pages of the first half of the novel (not directly, at least), but the whole story is totally engrossing from the very start. Dan is an engineer and a darn good one. His inventions have been designed with the view of easing the housework of women everywhere: Hired Girl cleans floors, Window Willie washes windows and Flexible Frank, his newest creation, will be able to do just about anything around the house, from changing a diaper to washing dishes. Life seemed to be treating Dan pretty well. Then his fiancee and business partner swindle him out of their business, and he decides to take the Long Sleep (cryogenic suspended animation) for 30 years so he can come back to chastise an ex-fiancee who will be 30 years older than he will be. Of course, he won't do it without his best friend Pete, his feisty, ginger ale-loving tomcat and true friend. He sends his remaining shares in the company he created to his partner's young daughter Ricky, his only other friend in the world, trying to make sure that those don't fall into the wrong hands as well. His only mistake is in confronting his traitorous friends one last time. He gets the Long Sleep all right, but he wakes up in 2000 without any money and without Pete. He starts trying to find Ricky and start a new life, but he eventually, prompted by subtle clues to things that will have taken place, works up a plan to journey back in time and change things -- of course, he won't really be changing things because they have actually already happened. It's so much easier to time travel when you know everything you will have done before doing it.

I love this novel. It's brilliant the way he works in clues to Dan's future past, and Heinlein's discussion of time travel is enough to make anyone a fanatic about the subject. When I think about time travel, I continue to think of this novel and its simple experimental analogies of coins and guinea pigs. It's mind-boggling yet completely comprehensible. I also love animals, and good old Pete is one of the most memorable feline characters in the universe of fiction.

Finally, the concept of the title is well-nigh epiphanous (if I may coin a word). Dan explains how Pete would make him open every door in his house whenever it snowed, convinced that behind one of those doors it will be summer time. Dan describes all of his adventures as his own search for the Door into Summer. The only possible explanation I can formulate as to why this novel did not win the Hugo for best science fiction novel of 1957 is the fact that Heinlein won the award the previous year for Double Star and could not comfortably be given the award two years in a row. The Door into Summer is much better than Double Star; in fact, it is much better than all but a handful of science fiction novels ever published.

- Rambles
written by Daniel Jolley
published 9 July 2005