This thesis examines the development of Arthur Koestler's
spirituality and ethics, from the publication of The Gladiators in 1939
to The Sleepwalkers twenty years later, drawing upon the extensive
material within Edinburgh's Koestler Archive.Where his work has often been divided into "political" and
"scientific" phases, this thesis adopts a unified approach based on the
single hierarchical system that arose from Koestler's analysis of human
freedom. The ethical trilogy - The Gladiators, Darkness at Noon and
Arrival and Departure - revealed Koestler's continuing abhorrence of
the deterministic philosophy he had espoused within the Communist
Party. After his abandonment of revolutionary ethics, Koestler proposed
an ethical hierarchy to understand the allegorical figures of his
eponymous essay, The Yogi and the Commissar.Arthur Koestler viewed society as constantly shifting between the
polar opposites of Yogi and Commissar. Hierarchical ethics sought to
transcend both poles. What emerged was a more optimistic, lifeenhancing
ethic than has hitherto been acknowledged. The work of
Richard Hillary, George Orwell and Michael Polanyi enabled Koestler to
refine his theory, the outcome of which was evident in the 1946 League
and the anti-hanging campaign a decade later.In his scientific writing, Koestler sought to understand the movement
of individuals within the hierarchy. If scientific models could be
utilised to explain moral and creative insight, he also become
convinced, earlier than one might suppose, that the evolution of the
human brain was the cause behind the failure of the species to ascend
the ethical hierarchy.Biological factors alone do not account for the irrational ethic that
survives Koestler's dystopic vision. The thesis presents evidence that
this ethical system contains an essential spiritual element traceable
to its author's mystical experience whilst imprisoned in Seville. Thus
the principle underlying his work and aspirations for humankind, postHiroshima,
is of a spiritual reality, the admission of which is
necessary before a holistic working ethic can be embraced
