What We Owe the Future - longtermism without the preaching

This book was much better than 80,000 Hours at explaining longtermism without just sounding boring and preachy. I’d been looking online for something similar after that one, and this seemed to fit. It earns a solid 4/5 from me.

I think it’s a great book for understanding this fairly modern philosophy. It had some interesting points, especially about utilitarianism and about “positive vs negative lives”.

One example that stuck with me: the author mentions that even though animals outnumber us significantly, if you compare neurons the numbers change drastically. Human population is 8 billion vs 135 billion farm animals, but if you compare neurons we have 700 million trillion compared to farm animals’ 20 million trillion. That’s about 35x the neurons in absolute numbers. From there comes a utilitarian point of view that maybe animals with more neurons are capable of feeling more joy or pain. So the net positivity of all humans being happy moves the utilitarian needle more than the net positivity of all farm animals, even though there are more of them. That argument didn’t change anything for me day to day, but it’s a thought I’m still processing. It made me feel a bit better about eating meat, and there might be some future ethics that grows from this theory which would be interesting to read more about.

So why not 5 stars? The prose could have been better, even less preachy, and easier to read. Immune by Kurzgesagt covers an even more complex topic and is much easier to read. And not every idea landed: the book pushes giving away lots of your income from a young age, but I still think it’s important for the young to build their wealth and look after their own family first.

These kinds of ideas are very hard to distill down, and this book tackles them in a way I found digestible. Overall I’m glad I read it, and philosophically it was interesting. If you want to know what effective altruism is and what it means, this is the one to read.