Categories and Toposes: Visualized and Explained

I haven't read through much of it yet, but it looks fantastic! The diagrams even have color. It's written in a very accessible way. The text mentions this and I strongly agree, you'll get the most mileage from watching Richard Southwell's Youtube videos. The book is self-contained, but from skimming it's apparent the text is much more technical whereas the videos have more examples and colloquial explanations.Also, not sure of the best place to report this, but there's a typo on page 130 about exponential objects. The text says f: C x A -> B, but the diagram shows f: C x B -> B.

I am a viewer of the youtube series and a graduate student in mathematics. Needless to say I pondered a few books on category theory but none are as clear, concise and explain in such crisp detail the way that this book does. Though I am only partly through it I would recommend to anyone who wants to learn category theory.

Easy to understand for beginners.

A comprehensive and clear introduction to category theory and toposes theory.

For the most part this text is intuitive and clear, but it is riddled with typos. This could have benefited from a further round of careful editing.

As a (mathematically inclined) software engineer learning from home, I haven't found it easy getting into category theory, but this book is making a huge difference. Most books on the subject just present each theorem with a minimal diagram and then move on to the next without comment. This book has many diagrams and each has a lot of detail. The authors also explain why each concept matters when it's presented, something which most other books just seem to draw a blank on. The subject matter itself isn't easy, so be prepared to stop and think a lot and experiment a lot on paper. But I find that with this book it's possible to keep pushing through without getting completely stuck, even without a tutor.

A very well-made book with a lot of illustrations to give you a feel of what's going on in Category Theory, it slowly progresses towards a higher level of abstraction, allowing the reader to adapt his speed to his level of comfort. Just a little critical remark, an index at the end of the book could have been helpful even though most of the key words can be seen in the table of contents (but of course not in an alphabetical order).