Daniel has published on diverse topics in nineteenth-century, twentieth-century, and contemporary cultural and intellectual history, including debates on evolutionary theory, the idea of degeneration, eugenics, social Darwinism, Victorian cultural attitudes to crime and madness, psychoanalytic though on war, and militarism, dreams, the myth of Svengali, the cult of Garibaldi, Italian nationalism, the literary representation of Rome, the fear of brainwashing, and methodological problems associated with psycho-biography, and the application of psychoanalytic thought to history. His recent books include: The Pursuit of the Nazi Mind: Hitler, Hess, and the Analysts (Oxford University Press, 2012).
Daniel holds a Senior Investigator grant from the Wellcome Trust for a project, entitled ‘Hidden Persuaders’: Brainwashing, Culture, Clinical Knowledge and the Cold War Human Sciences, c. 1950-1990‘ which explores the history of the human sciences and ‘psy’ professions during the Cold War.
Daniel is a Fellow of the Royal Historical Society and the British Psychoanalytical Society. He has written features and contributed to a variety of radio and television programmes, and online discussions, and has presented several radio documentaries for the BBC.