A standard account of how the sciences developed around 1900 tends to identify specialization and an increasingly strong pragmatic orientation as the driving forces shaping the sciences in this period. We want to oppose this account: Focussing on a number of inaugural lectures delivered at Dutch universities around 1900, we emphasize the prominence of integrative ideals, and the equally notable absence of references to specialization. The notion of unity upon which these ideals are based is extremely rich: the unity of a person, unity of education and research and unity within the system of the sciences all are aimed at simultaneously. Remarkably, this attitude is not a reactionary one, but is intimately related precisely to the emergence of new disciplines. The main goal of this paper is to establish the presence and the relevance, across the disciplines, of these integrative ideals. This leads to a number of important questions that need to be asked with respect to the dynamics of science in this period: how can the relevant notions of unity and harmony be conceptualized? and – a question not to be pursued here – how, then, did the ideal of specialization become as dominant as it appears to be today?