Isaacs was born in Nuremberg, Germany, (or Frankfurt)[1] in 1895, into a Jewish family of Russian background, who moved shortly to Switzerland.
[7] In April of that year, Robbins had dinner with the Isaacs', and found that Nathan was disillusioned with business, looking to retire and move to the country.
[9] Pyke and his family moved into the house containing the school, rented from Hugh Fraser Stewart, in Newnham village, a Cambridge suburb.
[10] The Isaacs' rented a flat on Hills Road, Cambridge in autumn 1924, but Nathan continued to work in London, where he spent most of the week.
[11] Jean Piaget, the Swiss educator and theorist with whose thought Susan and Nathan Isaacs were closely involved, paid a visit to the Malting House School in 1927.
[15] Nathan Isaacs continued to work as a metals merchant, and during World War II was a civil servant in the Ministry of Supply.
Susan knew of this relationship, and continued to relate well to Nathan intellectually: she concentrated on writing her book based on observations at Malting House.
[17][18] After the outbreak of World War II, Isaacs initially continued to work in London; while Susan was based in Cambridge.
[23] Isaacs gave evidence to the committee compiling the Plowden Report on education (commissioned 1963, published in 1967 after his death), as an authority on Piaget.
It appeared after his wife Susan died, as The Foundations of Common Sense (1949), bearing the subtitle "A Psychological Preface to the Problems of Knowledge".
[29] Clifford Geertz, writing of a lecture given by the philosopher George Raymond Geiger (1903–1998) on "cultural foundations of common sense", called it a "fine Deweyian subject".
[31] Isaacs wrote Children's Why Questions, as a response to, and criticism of, Jean Piaget's The Language and Thought of the Child (1924).
[32] The project was financed by Geoffrey Pyke, and resulted also in a 1927 anonymous editorial by Isaacs in Nature, under the title "Education and science", alluding to the curious child.
[36] By the early 1930s, Isaacs had joined the Aristotelian Society: he gave a paper there in 1931 that influenced the Essay on the Nature and Significance of Economic Science (1932) by Lionel Robbins.
A foreword to the 1972 edition, written by his widow Evelyn Lawrence, states that by this period Isaacs was mostly interested in philosophical topics: epistemology, ethics, logic.