What If?: Serious Scientific Answers to Absurd Hypothetical Questions

Book Preface

This book is a collection of answers to hypothetical questions.

These questions were submitted to me through my website, where—in addition to serving as a sort of Dear Abby for mad scientists—I draw xkcd, a stick-figure webcomic.

I didn’t start out making comics. I went to school for physics, and after graduating, I worked on robotics at NASA. I eventually left NASA to draw comics full-time, but my interest in science and math didn’t fade. Eventually, it found a new outlet: answering the Internet’s weird—and sometimes worrying—questions. This book contains a selection of my favorite answers from my website, plus a bunch of new questions answered here for the first time.

I’ve been using math to try to answer weird questions for as long as I can remember. When I was five years old, my mother had a conversation with me that she wrote down and saved in a photo album. When she heard I was writing this book, she found the transcript and sent it to me. Here it is, reproduced verbatim from her 25-year-old sheet of paper:

Randall: Are there more soft things or hard things in our house?

Julie: I don’t know.

Randall: How about in the world?

Julie: I don’t know.

Randall: Well, each house has three or four pillows, right?

Julie: Right.

Randall: And each house has about 15 magnets, right?

Julie: I guess.

Randall: So 15 plus 3 or 4, let’s say 4, is 19, right?

Julie: Right.

Randall: So there are probably about 3 billion

soft things, and . . . 5 billion hard things. Well, which one wins?

Julie: I guess hard things.

To this day I have no idea where I got “3 billion” and “5 billion” from. Clearly, I didn’t really get how numbers worked.

My math has gotten a little better over the years, but my reason for doing math is the same as it was when I was five: I want to answer questions.

They say there are no stupid questions. That’s obviously wrong; I think my question about hard and soft things, for example, is pretty stupid. But it turns out that trying to thoroughly answer a stupid question can take you to some pretty interesting places.

I still don’t know whether there are more hard or soft things in the world, but I’ve learned a lot of other stuff along the way. What follows are my favorite parts of that journey.

randall munroe

Download Ebook	Read Now	File Type	Upload Date
Download Now here		Epub	May 30, 2020