In November 1919, Piaget moved to Paris. There he found much material for work and reflection, attending several courses at the Sorbonne and also in hospitals, given by philosophers and psychiatrists. This was a period of training and of invention at the same time. Under the direction of Dr. Théodore Simon, he devoted himself to the standardization of psychological tests and had the opportunity to practice at the École de la Grange-aux-Belles, where he developed his clinical method for interviewing children, in September 1920. Much of his future publications will be based on this strategy of empirical inquiry.
April 1923… Jean Piaget married Valentine Châtenay, granddaughter of the President of the Swiss Confederation, Paul Cérésole. After the celebration of the wedding in Lausanne, the couple got on their bicycles to go for their honeymoon in Valais.
In September 1925, the doctor and psychologist Ignace Meyerson, who was very close to the Piaget family, went to spend about ten days’ with them in a villa in Salvan les Granges.
In the late 1920s, to confront growing tensions in Europe, intellectuals organized a series of conferences in Davos, Switzerland, with the aim of a French-German approach. Jean and Valentine Piaget participated in March 1928 and met various French and German thinkers and scholars, including Albert Einstein.
In early September 1929, Piaget made its first intercontinental voyage on a transatlantic ship. He attended the 9th International Congress of Psychology at Yale University, USA, where he met psychologists such as Charlotte Bühler, Kate Wolf, Kurt Lewin, Arnold Gesell. Among them was Alexandre Luria, who recommended Vygotski’s work.
From 1925 to 1940, the Piaget family travelled to the mountains to rest during the holidays. For Christmas, in 1929, they were in Lens sur Granges, in the Valais region.