The beginning of the twentieth century was a period of great upheaval in physics, as new theories and discoveries threatened the very concepts which the discipline was founded upon. One such concept was that of continuity, as Planck’s theory of the quanta implied that not just matter, but energy too, was discontinuous. At the 1913 British Association meeting, Oliver Lodge devoted the majority of his presidential speech to defending continuity, and called for a ‘conservative attitude’ in the face of the new physical theories. His speech highlights the fragmented state the British physical community was in during this period, with conflict between past and present theories, and between the newly defined categories of classical and modern. Exploring the case study of this notion of continuity in energy and matter, this paper finds parallels with the wider debates surrounding continuity of ideas in the transition from classical to modern physics. Were the older ideas entirely superseded by the new, or, as some argued, merely adapted and extended? How did physicists of the older generation, such as Lodge, define themselves, and their physics, against the new community of 'modern' physicists? I also explore the developments of these debates in the public sphere in early twentieth century Britain.