“One of the major problems encountered in time travel is not that of becoming your own father or mother. There is no problem in becoming your own father or mother that a broad-minded and well-adjusted family can't cope with. There is no problem with changing the course of history—the course of history does not change because it all fits together like a jigsaw. All the important changes have happened before the things they were supposed to change and it all sorts itself out in the end.The major problem is simply one of grammar, and the main work to consult in this matter is Dr. Dan Streetmentioner's Time Traveler's Handbook of 1001 Tense Formations. It will tell you, for instance, how to describe something that was about to happen to you in the past before you avoided it by time-jumping forward two days in order to avoid it. The event will be descibed differently according to whether you are talking about it from the standpoint of your own natural time, from a time in the further future, or a time in the further past and is futher complicated by the possibility of conducting conversations while you are actually traveling from one time to another with the intention of becoming your own mother or father.Most readers get as far as the Future Semiconditionally Modified Subinverted Plagal Past Subjunctive Intentional before giving up; and in fact in later aditions of the book all pages beyond this point have been left blank to save on printing costs.The Hitchhiker's Guide to the Galaxy skips lightly over this tangle of academic abstraction, pausing only to note that the term "Future Perfect" has been abandoned since it was discovered not to be.”

“One of the main problems encountered in time travel is not that of accidentally becoming your own father or mother. There is no problem involved in becoming your own father or mother that a broadminded and well-adjusted family can’t cope with.”

“Your past is not as important as your future. Did you know that? Can't change anything about what you've been, but you can change who you'll become.”

“At times it may seem as though you and your past are one. Sometimes we fail to differentiate between what has happened to us and who we are today. If you have a hard time getting beyond that damaging mind-set let me encourage you right now. You are not your past Although you are changed and shaped by past experiences who you were yesterday does not control the person you have the potential to become tomorrow.”

“I hadn't gotten old enough yet to realize that living sends a person not into the future but back into the past, to childhood and before birth, finally, to commune with the dead. You get older, you puff on the stairs, you enter the body of your father. From there it's only a quick jump to your grandparents, and then before you know it you're time traveling. In this life we grow backwards.”

“My heart clutched - it was one of those moments when you feel time is a rug that's been yanked out from under you; everything around you has changed so gradually that it is only all at one you look up and realize how different your life has become.”