Placeholder Math Equations That Changed the World Notebook - Hardcover – Cognitive Surplus

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Equations that Changed the World Hardcover Notebook - Dot Grid

$ 24.95
13 reviews
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This deep blue and burnt orange notebook is inspired by the equations that have changed the world. The Pythagorean Theorem, five regular solids, the Theory of Proportions, sphericity of the Earth, are just a few among many scientific and mathematical discoveries credited to the early Greek philosopher Pythagoras. Channel his innovative spirit as you take notes in this hardcover journal from your physics class, graph your findings or keep track of your data.

Carbon Neutral Shipping & Operations
100% Recycled Paper
Compostable Packaging

The textured covers of these notebooks have the feel of old textbooks, and with advanced lay-flat pages, they want to fall open, like a well-loved library book. Go ahead and see for yourself – these are the notebooks your most brilliant ideas have been waiting for.

The Hypothesis series is built with high-quality 100% recycled paper and printed with soy inks, leaving a light footprint. Be inspired to ask the right questions, connect the dots (even when they’re really far apart), and keep pushing humanity forward, so that tomorrow is always brighter than today.

7" x 9"
Page Count
192 pages (96 sheets)
Paper Type 5mm Dot Grid
Paper Weight 81 gsm
Binding Lay-flat Hardcover
Paper Composition Acid-free
100% recycled
100% post-consumer waste
Printing Soy-based ink
Origin Designed in Oregon
Paper milled in Japan
Assembled responsibly in China


For more information on our paper, see the blog.

••• Holiday 2023 Shipping Dates & Deadlines ••• 


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Peer Reviews

Customer Reviews
4.8 Based on 13 Reviews
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Filter Reviews:
Abraham P.
United States United States

Great product

High quality product and well made. Great design. It is exactly as it seems on the picture

Victor V.
United States United States

In my not-so-humble opinion,

These are outstanding notepads. The problem I have with them is that the tiny dots are too faint to be visible in locations that are not well lighted. I like to draw electronic schematics and the dots will not serve their purpose. (I use 1/4" graph paper.) I am not asking for a refund because I think they are a beautiful work of art and I will give them to persons who will appreciate them.

A Cognitive Surplus Customer
Mabel R.
United States United States

The Perfect Notebook

I love these notebooks so much! Perfect size. The dot grid is so light they’re basically unlined. They really do lie open on their own without flopping back closed. The hardcover makes them super-durable. I buy a new one for every project I start. Plus such fun graphics!

Adam S.
United States United States

this review

The best part of this journal was the quality of the quality; the worst part was having to write this infernal review.

Ada W.
United States United States

Awesome Notebook!

I first saw these notebooks at a science conference in Seattle and did not buy one then- and what a mistake that was! I recently ordered this notebook to journal in and it has so far surpassed my expectations. The cover is beautiful and interesting, and the pages are very good quality. My pen does not bleed through at all. Overall a very nice notebook that I would highly recommend!

Gustavo M.
United States United States

Beautifully designed and made

This was the first Cognitive Surplus notebook that catched my eye and I made no mistake ordering it. It is beautifully designed and made. I'm sure I will enjoy it for a long time. Highly recommended.

Sarah C.
United States United States

Familiar and Foreign

It's hard to describe why I like these designs when the first thought that comes to mind is, "I just like it." It makes me wish this was available during high school to convince me I could love art and science together, or pursue creative writing and STEM at the same time without a conflict of interest. At least I know the truth now! You can indeed love both.

A Cognitive Surplus Customer
Kadisha V.
United States United States

Best Notebook I Ever Had

The dot grid lining is certainly an adventure to use. It doesn't take away as easily from the challenge of writing straight in the lines like I thought it would with its minimalist outline, and it looks cleaner, putting more focus on your writing than the lines between. Like a succinct method of organizing your thoughts. Then there's the lovely, neat feel of the notebook, itself. The creation of the hardcover was amazingly handled, and the designs are lovely, like a collage of artworks that stand out separate from one another but also blend in with one another like the best piece of "white noise" visuals I've ever had the pleasure of laying my eyes on. Overall, because the paper has the added bonus of not smudging all that easily, from what I have observed thus far, these notebooks, if all made in the same quality (which I don't doubt - the creators of these books know what they're doing), deserve their five star ratings. 10/10 would buy, again. I'm excited to try buying some more come the Fall semester.

Jessie G.