Essays on Education and Kindred Subjects: Everyman's Library
Essays: Scientific, Political, & Speculative; Vol. 1 of 3: Library Edition (1891), Containing Seven Essays not before Republished, and Various other Additions.
Essays: Scientific, Political, & Speculative; Vol. 3 of 3: Library Edition (1891), Containing Seven Essays not before Republished, and Various other Additions.
First Principles
Illustrations of Universal Progress: A Series of Discussions
The Data of Ethics
The Factors of Organic Evolution
The Philosophy of Style
The Principles of Biology, Volume 1 (of 2)
The Right to Ignore the State