[About the Book]
“If only I could go back to the past.”
“If only I hadn’t made that choice.”

Without realizing it, many of us live with the quiet illusion of a time machine in our hearts.
This book directly challenges that universal dream-the idea of traveling back in time. Drawing on philosophy, physics, and the history of scientific thought, it explores from multiple perspectives why traveling to the past is fundamentally impossible.
Rather than treating time machines as a work of science fiction, the book reframes the discussion as a set of deeper questions:
What is time?
What is causality?
How should we live as human beings?

Yet this is not merely a rejection of time travel.
“The past cannot be changed. And yet, we can change the meaning of the past.”
This insight forms the very heart of the book.

“Farewell, time machine! We choose to live toward tomorrow!”
Only by letting go of illusion can we begin to truly live in the present. Through the lens of science and philosophy, this book offers a sincere and thoughtful guide to one essential question:
If we cannot return to the past, how should we live?
Accessible even to readers without a background in science or philosophy, this is a work that invites you to reflect on time, life, and meaning as your own personal questions.

[About the Author]
Tadashi Chiyojima
Born in Fukuoka Prefecture in 1951.
1974 – Graduated from the Philosophy Program, Faculty of Letters, University of Tokyo.
Subsequently completed the doctoral course in the Graduate School of Humanities at the same university.
Currently Associate Professor at Tokyo Metropolitan Institute of Technology.
Major works include Explorations of Spacetime (Hokuju Publishing),
Humanity’s Counterattack (Koyo Shobo),
Einstein: The End of the “Twin Paradox” (Tokuma Shoten),
and The Collapse of Common Sense about Entropy! (Koyo Shobo), among others.