Addis attended the University of Oxford to read History for two years before having to cease her studiesleave due to illness.<ref name=":1" /> Nevertheless, she afterwards spent five years working with Professor Charles Waley-Singer cataloguing the [[alchemy|alchemical]] manuscripts of the British Isles. After this period of time and upon deciding that she did not wish to continue working with manuscripts, Addis attended the London School of Economics with the idea of pursuing teaching and child psychology.<ref name=":1" /> While attending lectures on child psychology at LSE, Addis was introduced to the study of child guidance and applied to study what was then LSE's Mental Health Course. Due to credits from previous studies at LSE and practical experience before enrolling, Addis was able to skip the normal to year Social Science diploma that was expected from the course. She qualified from this course in 1933.<ref name=":1" />
