In 1946 Astbury presented a paper at a symposium in Cambridge in which he said: "Biosynthesis is supremely a question of fitting molecules or parts of molecules against another... one of the great biological developments of our time is the realisation that probably the most fundamental interaction of all is that between the proteins and the nucleic acids". He also said that the spacing between the nucleotides and the spacing of amino acids in proteins "was not an arithmetical accident".