What is a number?: mathematical concepts and their origins

Mysticism, number, and geometry : an introduction to Pythagoreanism

The Elgin Marbles and Plato's geometric chemistry

An introduction to infinity

The flat Earth and the spherical sky

Theology, logic, and questions about angels

Time, infinity, and incommensurability

Medieval theories of vision and the discovery of space

The shape of space and the fourth dimension

What is a number?

The dual nature of points and lines

Modern mathematical infinity

Elegance and truth.