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A Guide to Making Friends in the Fourth Dimension
Discover the joy of higher dimensions in this whimsical guide, complete with color illustrations. Toby Hendy invites readers on a journey navigating the mysteries of four-dimensional space alongside imaginative characters. These encounters are inspired by Hendy's creative videos uploaded to YouTube and TikTok. Includes a foreword by Michael Stevens (Vsauce) and a guest chapter by CodeParade.
240 pages, Paperback
Published November 4, 2025
35 people are currently reading
94 people want to read
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October 2, 2025My favorite thing about math is that we just…made it up.
This was silly but also thought provoking.
This was silly but also thought provoking.
September 8, 2025
I’m not sure I’ll ever think about our physical dimensions the same again, and I’m ok with that. As I type here on my two dimensional keyboard with text showing up on this plane that is the review text box, I think about how that would translate to higher dimensionality, and typing in 3d within a volumetric review space. Toby has done a phenomenal job taking something so mind boggling and showcasing it in a way that maybe, just maybe, starts to make sense to our 3d brains.
This was the perfect mix of story and illustration, without so much math as to be overwhelming, I would recommend this to anyone remotely interested in learning more about dimensions, regardless of any mathematical background. That said, as someone with a math and physics background, I was captivated the entire time!
This was the perfect mix of story and illustration, without so much math as to be overwhelming, I would recommend this to anyone remotely interested in learning more about dimensions, regardless of any mathematical background. That said, as someone with a math and physics background, I was captivated the entire time!
September 24, 2025
Ha valakit érdekel a több dimenziós matematika, egy leírás arról, milyen lehet az élet 2 vagy 4Dben, és tömören az ebből következő elméleti asztrofizika, és nem csak azt akarja elmondani, hogy elolvasott a témában egy könyvet, hanem valami szeretne is felfogni ebből az egészből, annak 112%-ban ajánlom Toby könyvét (és a YouTube-csatornáját is). A színes illusztrációk és a szöveg okos analógiái sokat adnak a befogadhatósághoz. Olvasmányosabb, mint Hawking, de Toby után Az idő rövid története is jobban fog csúszni.
October 9, 2025
"If time is a dimension that persists, you could imagine observing all of time and space laid out before you. Yet, our experience is constrained to the fleeting moment of now."
I actually haven't seen any of Toby's mathematics videos on YouTube. My introduction to Toby was through Jet Lag, and I love so much when she joins a season that I wanted to support her by purchasing this book and exploring this entire other world she lives in.
I will admit she lost me MANY times. I only took Algebra II in high school and pursued a BA instead of a BS for a reason. But this book was sweet, encouraged me to stretch, and gave me moments of childlike wonder. Thanks, Toby.
I actually haven't seen any of Toby's mathematics videos on YouTube. My introduction to Toby was through Jet Lag, and I love so much when she joins a season that I wanted to support her by purchasing this book and exploring this entire other world she lives in.
I will admit she lost me MANY times. I only took Algebra II in high school and pursued a BA instead of a BS for a reason. But this book was sweet, encouraged me to stretch, and gave me moments of childlike wonder. Thanks, Toby.
September 17, 2025
a delight! 4.5:)
September 9, 2025
Review of A Guide to Making Friends in the 4th Dimension by Toby Hendy
Toby Hendy’s A Guide to Making Friends in the 4th Dimension is less a textbook than a playground of imagination. It’s a richly illustrated, exuberant invitation to think beyond the ordinary, to stretch one’s intuition toward the strange territory of higher dimensions.
The book is structured as a series of thought experiments that take the reader on a whimsical journey: from the playful geometry of Twosville, through the oddities of Threesville, and finally into the shimmering, elusive world of the fourth dimension. The table of contents alone is a carnival of curiosity — “Hypersphere Soup,” “How to Draw a Tesseract,” “The Woman Who Flipped Out.” Each chapter feels like a stage set for Hendy to ask, “What if?”
What makes the book immediately striking are its lavish color illustrations. Hendy clearly delights in visual metaphors, looping spirals and dazzling diagrams that often feel more like art than pedagogy. This choice makes the book unusually accessible: you don’t need advanced mathematics to follow along, only a willingness to picture and wonder.
That accessibility, however, comes with trade-offs. Hendy is not aiming for scientific rigor. At times, her reliance on the old Flatland-style device of two-dimensional beings “seeing” their world can mislead more literal-minded readers. Abbott used such conceits for satire; Hendy uses them for science play. The result is charming, but occasionally shaky if read as physics rather than allegory. Readers expecting solid geometry or theorems will not find them here.
Yet it would be unfair to measure this project by the yardstick of a textbook. This is a passion project, self-published, likely never to turn a profit — and proudly so. It’s less about profit or precision than about communicating sheer delight in the possibilities of thinking differently. Hendy even signs pre-ordered copies by hand, which suits the personal, artisanal spirit of the whole endeavor.
In the end, A Guide to Making Friends in the 4th Dimension is best approached as a love letter to curiosity. It’s a book for those who remember the thrill of their first mind-bending science video, or who enjoy the philosophical playfulness of imagining creatures in Flatland bumping into higher truths. If you want rigor, you’ll need to look elsewhere. But if you want to feel the author’s joy in wondering about impossible spaces, this book delivers.
Verdict: A colorful, eccentric, and heartfelt guide for anyone who wants to think sideways into the fourth dimension. Not a manual of science, but a celebration of curiosity.
Toby Hendy’s A Guide to Making Friends in the 4th Dimension is less a textbook than a playground of imagination. It’s a richly illustrated, exuberant invitation to think beyond the ordinary, to stretch one’s intuition toward the strange territory of higher dimensions.
The book is structured as a series of thought experiments that take the reader on a whimsical journey: from the playful geometry of Twosville, through the oddities of Threesville, and finally into the shimmering, elusive world of the fourth dimension. The table of contents alone is a carnival of curiosity — “Hypersphere Soup,” “How to Draw a Tesseract,” “The Woman Who Flipped Out.” Each chapter feels like a stage set for Hendy to ask, “What if?”
What makes the book immediately striking are its lavish color illustrations. Hendy clearly delights in visual metaphors, looping spirals and dazzling diagrams that often feel more like art than pedagogy. This choice makes the book unusually accessible: you don’t need advanced mathematics to follow along, only a willingness to picture and wonder.
That accessibility, however, comes with trade-offs. Hendy is not aiming for scientific rigor. At times, her reliance on the old Flatland-style device of two-dimensional beings “seeing” their world can mislead more literal-minded readers. Abbott used such conceits for satire; Hendy uses them for science play. The result is charming, but occasionally shaky if read as physics rather than allegory. Readers expecting solid geometry or theorems will not find them here.
Yet it would be unfair to measure this project by the yardstick of a textbook. This is a passion project, self-published, likely never to turn a profit — and proudly so. It’s less about profit or precision than about communicating sheer delight in the possibilities of thinking differently. Hendy even signs pre-ordered copies by hand, which suits the personal, artisanal spirit of the whole endeavor.
In the end, A Guide to Making Friends in the 4th Dimension is best approached as a love letter to curiosity. It’s a book for those who remember the thrill of their first mind-bending science video, or who enjoy the philosophical playfulness of imagining creatures in Flatland bumping into higher truths. If you want rigor, you’ll need to look elsewhere. But if you want to feel the author’s joy in wondering about impossible spaces, this book delivers.
Verdict: A colorful, eccentric, and heartfelt guide for anyone who wants to think sideways into the fourth dimension. Not a manual of science, but a celebration of curiosity.
December 4, 2025
If you’ve ever felt socially awkward in three dimensions, this is the book for you - because in four dimensions, the very notion of »awkward« gets delightfully scrambled. Toby Hendy doesn’t just write a math book: she throws open the doors to a mathematical funhouse filled with mirror-worlds, fractals, brain-stealing four-dimensional creatures (and yes, metaphoric brain-peering), and invites you to waltz in.
The charm of the book lies in its mixture of whimsy and clarity: complex ideas from theoretical physics and higher-dimensional geometry are wrapped in storytelling, humor, and - delightfully - colorful illustrations that make even a tesseract seem like a friendly neighbor. You don’t need to be a hardened mathematician (or even remember high-school algebra) to follow along - Hendy writes with the ease of a friend showing you a weird but beautiful magic trick.
At its best, the book does more than show you what a fourth dimension is — it makes you imagine what it feels like to dance through it. At its quirkiest, it suggests that maybe, just maybe, a four-dimensional being doesn’t need a key to pick a lock (gems from a safe, anyone?).
If you’re a curious mind — whether a math enthusiast, a complete beginner, or something in between — this little guide is a delightful handshake with the fourth dimension. Read it, and you might come away not only smarter, but a tiny bit more comfortable with the weird, the abstract, and the wonderfully impossible.
The charm of the book lies in its mixture of whimsy and clarity: complex ideas from theoretical physics and higher-dimensional geometry are wrapped in storytelling, humor, and - delightfully - colorful illustrations that make even a tesseract seem like a friendly neighbor. You don’t need to be a hardened mathematician (or even remember high-school algebra) to follow along - Hendy writes with the ease of a friend showing you a weird but beautiful magic trick.
At its best, the book does more than show you what a fourth dimension is — it makes you imagine what it feels like to dance through it. At its quirkiest, it suggests that maybe, just maybe, a four-dimensional being doesn’t need a key to pick a lock (gems from a safe, anyone?).
If you’re a curious mind — whether a math enthusiast, a complete beginner, or something in between — this little guide is a delightful handshake with the fourth dimension. Read it, and you might come away not only smarter, but a tiny bit more comfortable with the weird, the abstract, and the wonderfully impossible.
December 1, 2025
This book is absolutely amazing. It’s written as a beautiful story in which you travel into different worlds of different dimensions. You’ll explore 2D, 3D and even 4D creatures’ lives and own perceptions of the world as well as what an interaction between these dimensions would mean, both from a physical perspective and from a social and cultural perspective.
It’s such an easy read about such a complex topic. You can actually sit back and relax while you explore the wonders of higher and lower dimensions. You’ll learn so much and start to wonder why you’ve never thought of 2D brains, digestive systems and… doors. 2D doors are more complicated than you’d think!
The illustrations are simply beautiful and all the characters in the book are so cute and interesting. This book has really brought the fourth dimension closer to me; I can feel its presence a tenth of a millimeter away from me. Now, please, excuse me while I try to figure out where that beautiful smell of berries is coming from!
It’s such an easy read about such a complex topic. You can actually sit back and relax while you explore the wonders of higher and lower dimensions. You’ll learn so much and start to wonder why you’ve never thought of 2D brains, digestive systems and… doors. 2D doors are more complicated than you’d think!
The illustrations are simply beautiful and all the characters in the book are so cute and interesting. This book has really brought the fourth dimension closer to me; I can feel its presence a tenth of a millimeter away from me. Now, please, excuse me while I try to figure out where that beautiful smell of berries is coming from!
December 4, 2025
A lighthearted but ambitious book. I think it matches its predecessors like Flatland in digging for surprising examples of the effects of accessing different numbers of dimensions, and does a great job of presenting those examples.
I do find that the book struggles to follow a single thread however. Though the boat metaphor, and the multi-dimensional burglar story, are attractive, I felt that we are hopping from island to island in terms of ideas without really unifying them all.
That said, there are glimpses of this unifying idea, which I feel is the attempt to find a way to train our intuition to move from one n-dimensional world to another, and it is commendable that this difficult idea is presented in such a friendly way, with so many illustrations. I would like to see further research and effort along these lines.
I'm going to be hard on it and give it 3 stars, though I would like to put 3.5. I remain happy I bought it and will recommend it to my three-dimensional friends.
I do find that the book struggles to follow a single thread however. Though the boat metaphor, and the multi-dimensional burglar story, are attractive, I felt that we are hopping from island to island in terms of ideas without really unifying them all.
That said, there are glimpses of this unifying idea, which I feel is the attempt to find a way to train our intuition to move from one n-dimensional world to another, and it is commendable that this difficult idea is presented in such a friendly way, with so many illustrations. I would like to see further research and effort along these lines.
I'm going to be hard on it and give it 3 stars, though I would like to put 3.5. I remain happy I bought it and will recommend it to my three-dimensional friends.
September 11, 2025
I love this book! Toby explains complicated concepts in the most understandable and fun way possible. It really shows knowing science and being a science communicator are two entirely different things. She’s able to bridge the knowledge gap for the reader with fun analogies and stories, holding your hand the whole time and making you feel much smarter by the end of the book.
I’d highly recommend this book for students in high school or new to university, seems like a good age to have enough knowledge to dive into the world of dimension. There are also hints of linear algebra and calculus in there without getting too much into the nitty-gritty details, but still helps with visualizing many of the interesting concepts. I wish I had this book when I was a teenager!
(I love Tudy so much, and the final twist *gasp* she’s two-dimensional Toby all along!)
I’d highly recommend this book for students in high school or new to university, seems like a good age to have enough knowledge to dive into the world of dimension. There are also hints of linear algebra and calculus in there without getting too much into the nitty-gritty details, but still helps with visualizing many of the interesting concepts. I wish I had this book when I was a teenager!
(I love Tudy so much, and the final twist *gasp* she’s two-dimensional Toby all along!)
November 6, 2025
Excellent perhaps first book by YouTuber & math/science communicator Toby Hendy who I believe has an asteroid named after her! I particularly enjoyed the earlier I believe in the book idea of 2d chirality so for instance I believe formic acid isn’t chiral in our 3d world but having one plane of symmetry there etc wow not an expert anyway it ends up being in 2 possible configurations in a hypothetical 2 universe so arguably 2d chiral… also sphere I believe in box BUT in higher dimensions what the names become how much volume in however many dimensions is interesting too for the unit sphere I suppose I recall-I’m definitely trapped in 3 dimensions BUT a little bit less after having ordered this book indeed - infinitely many stars IF she writes an infinite dimension fractal focused beyond what she already wrote sequel etc!⭐️♾️
September 14, 2025
A good introduction to ideas about worlds with a different number of spatial dimensions. You don't need to know any particular physics or math to enjoy this book. The writing style is conversational and flows right along.
I'd been thinking about some math-related books I'd read before, like The Planiverse by A.K. Dewdney and logic puzzle books by Raymond Smullyan, and so this book caught my attention. A number of ideas that I don't think I'd encountered in other works before were quite neat to think about, including how vision in other spatial dimensions would work, differences in chemistry, and the unsettling implications of being flipped when crossing to and from worlds with a higher number of spatial dimensions.
I'd been thinking about some math-related books I'd read before, like The Planiverse by A.K. Dewdney and logic puzzle books by Raymond Smullyan, and so this book caught my attention. A number of ideas that I don't think I'd encountered in other works before were quite neat to think about, including how vision in other spatial dimensions would work, differences in chemistry, and the unsettling implications of being flipped when crossing to and from worlds with a higher number of spatial dimensions.
September 9, 2025
This book is fantastic! I am a long time fan of Hendy’s work on YouTube and such, and coming from a mathematical/physics background myself I was quick to preorder. The book does a fantastic job of showing different dimensions in a more intuitive and creative way that long, complex mathematical formulae. I even read some of my favourite parts to my partner (who is not so mathematically inclined) and not only did it help her to understand what I mean when speaking about dimensions, but she also really enjoyed it! Plus there are cats mentioned - we love cats!
December 3, 2025
This is a delightful book of storytelling and maths.
Toby is a wonderful guide making the truly complex approachable in a beautifully presented book - lovely illustrations and always approachable. I love how all the examples here are so specific - 'hyperspherical pufferfish' and 'universe soup'.
I suspect this is just the start of her journey as an author and I'm here for the ride, regardless of how many dimensions it goes through.
Toby is a wonderful guide making the truly complex approachable in a beautifully presented book - lovely illustrations and always approachable. I love how all the examples here are so specific - 'hyperspherical pufferfish' and 'universe soup'.
I suspect this is just the start of her journey as an author and I'm here for the ride, regardless of how many dimensions it goes through.
December 7, 2025
It is quite amazing how easy Toby made it for kids of all ages to get the concept of dimensions. Toby (Tibees) is one of my favorite Youtubers, so I preordered this book as soon as she announced it. After reading it I gave it to my grand-daughters who are perfectly challenged by it. I love how Toby makes the girls struggle just enough to end up loving the read and getting hooked on understanding dimensions. I have since ordered 4 more copies for my favorite librarians.
September 7, 2025
I’ve read a lot of books on Dimensions, and this one is by far and away the best. 10/10 recommend - especially if you’re learning about the topic for the first time. She even has a very high quality ‘recommended reading’ section at the end. Very fun, very intuitive, very visual, and very colorful! Thanks Toby!!!
November 23, 2025
Quite nice, a playful dive and imaginative. "The Long Earth" might be spotted aboard the Pink Vessel. Really surprising to see that work of fiction grounded by a (presumably) wholly independent creation. The mathematics here are conceptual, which suits me rather well. I'm not mentally fit for writing through vectors, matrices or even the basic Euclidean forms, not without a guide.
December 4, 2025
Really love this book. It is quirky, informative, mind bendy!! Highly recommend to all and everyone. What a great resource for curious teachers to offer to their curious students. And not really an age barrier. Put this book in schools, rest homes, libraries (anywhere people have time to sit for a bit) and allow our awe, wonder, imagination to be ignited😃
November 1, 2025
Hendy presents the first, second, third, fourth dimensions and beyond with her usual gentleness, creativity, and panache. I enjoyed the variety of dimensional situations and characters she came up with. This is a cozy and accessible primer on understanding dimensionality.
October 23, 2025
Really accessible guide to quite deep scientific concepts. Well written and well illustrated.
November 6, 2025
Toby SIMPLY bridges the gap for the educated and the one's who thrive to be educated.
This book is another great example of her generosity and endless energy.
Sincerely,
InvenTodd
This book is another great example of her generosity and endless energy.
Sincerely,
InvenTodd
November 13, 2025
approachable, engaging, and thoroughly enjoyable!
December 4, 2025
Beautiful book! Colour illustrations help us visualise tricky high-dimensional concepts. It has a good mix of cute stories and math, perfect gift for that math prodigy you know, or any deep thinker.
December 5, 2025
This book opened up my fourth dimension to visualize stuff!
October 30, 2025
I have followed Toby's work on Youtube almost from the start and I bought this because I wanted to continue supporting her as a way to thank her for all of the work she has done and the contributions she has made to the community. This is a perfect extension of her work and is a fun easy read as well. The art work is fantastic, extremely clever and well done, the little mini adventures are very useful tools to help the reader visualize the concepts she is explaining. However, one of my favorite parts is I received one of the copies with "Tudy" drawn in it. I can't wait to see what she produces in the future.
Displaying 1 - 25 of 25 reviews