Mathematical legacy

This chapter re-examines Dodgson’s achievements during his lifetime, and how some of them resurfaced in the 20th century. The chapter is divided into subject areas: geometry (including his alternative version of Euclid’s parallel postulate), trigonometry (for which he devised a new set of symbols), algebra (his work on determinants), logic (where the work of Bartley and others has led to a significant re-evaluation of Dodgson’s involvement), voting theory (on which he was in contact with a number of senior politicians), and probability, and concludes with a section on ciphers and cryptology. There has been a growing interest by scholars in Dodgson’s serious mathematical work since the third quarter of the 20th century, particularly as more of it has been published.