Auguste Comte

The philosophy of Mathematics

Cours de philosophie positive ( 1 , 2 , 3 , 4 , 5 , 6 ) – French

Herbert Spencer

The Right to Ignore the State

Essays on Education and Kindred Subjects

The Data of Ethics

The Principles of Biology

Essays: Scientific, Political, & Speculative ( 1, 2, 3  )

Illustrations of Universal Progress

The Factors of Organic Evolution

Les bases de la morale évolutionniste ( French )

J S Mill

Auguste Comte and Positivism by John Stuart Mill