The International Auxiliary Language Association (= IALA) was formed in 1924 to conduct neutral investigation and research in the field of auxiliary language. Under the able direction of its Hon. Secretary, Mrs. Dave Hennen Morris of America, IALA attracted many scientists and practising linguists and with their co-operation elaborated the principles of and the basis for the best form of a neutral, constructed, auxiliary language. In 1925 Otto Jespersen met Mrs. Dave Hennen Morris in Switzerland; here started a long and fruitful collaboration between Jespersen and IALA. Two years later a meeting was arranged between Mrs. Morris, Prof. Jespersen, and Prof. W. E. Collinson (University of Liverpool) a close collaborator and later director of research of IALA. Discussion took place on theoretical linguistic problems and on the programme of IALA which outlined the plans for a number of years.
After this conference Jespersen decided to give definite shape to his ideas on particular aspects of the language problem. When he found encouragement both from Prof. Collinson (a member of the Esperanto movement) and from Dr. S. Auerbach (a member of the Ido movement) he began the work and published his book in 1928 under the title An International Language (Allen & Unwin). Jespersen is not content to state the rules only, he discusses certain points and compares them with other systems and he is sufficiently objective to state certain shortcomings for which he was unable to find a better solution. Dr. S. Auerbach offered in the initial stages to translate the book into German and later furnished the translation Eine internationale Sprache (Heidelberg). This grammar was followed by Novial Lexike in 1930.
In 1930 Jespersen convened, on behalf of IALA, and presided over a meeting of linguists and interlinguists in Geneva which had an informal character and which it was hoped would prepare the ground for future co-operation between linguists and the various schools of auxiliary language.
At the congress of linguists (Geneva, 1931) Jespersen reviewed, for the secretariat, the answers to a questionnaire which had invited opinions on the desirability of an international auxiliary language. This gave him the opportunity to refute many old arguments against and international auxiliary language. Sechehaye, the general secretary of the congress, said that "to judge from the answers and opinions received, one could now speak of the solemn rehabilitation of artificial languages ... science will contribute its share towards an evolution which is necessary and which will, one day, lead to a solution." (Novialiste, March, 1938).
Meanwhile Jespersen joined Prof. Collinson and Prof. Sapir, as well as Helen S. Eaton as linguistic research associate, on the Advisory Board for Linguistic Research of IALA.
On the occasion of the 4th International Congress of Linguists which was to take place in Copenhagen, in 1936, IALA invited the participants to a preliminary meeting to discuss the problem of an international auxiliary language and its own long-term programme, its past work of research, and its draft of criteria for an international language. Again Jespersen and other members of IALA's staff took an active part in the proceedings and so prepared the ground for a gradually increasing interest for IALA's plans among the linguists of the world. (Men labore por un international lingue, Novialiste, 18, 1937; 19, 1938).
In a series of lectures on the `Development of Language' at University College, London, in 1920, Otto Jespersen reviewed the work for an international language and unhesitatingly recommended Ido. This was only a few years before he published his own system. He had never given up this work and has devoted much time during his life for the advancement of an international auxiliary language. This question was dear to him and he saw its practical application and potential possibilities, as well as the urgent necessity for its solution.
It is to IALA's merit to have drawn Jespersen into active participation in the work for the auxiliary language, for the proposals which he crystallized in Novial are a valuable contribution of a professional linguist. Many principles of Novial and much of the grammatical structure confirm what has been defined for Ido under his own active participation and the collaboration of many other experienced interlinguists. The differences between Ido and Novial are small and we may justifiably hold the belief that the final auxiliary language cannot be far from either and is likely to incorporate the best points of both languages.