Studies of network forming oxide liquids are combined with studies of network-forming chalcogenide glasses to demonstrate a universal dependence of the glass forming fragility on the topological connectivity of the network. This connection between structure and dynamics is congruent with theoretical predictions for a rigidity transition near an average bond number of 2.4 and the common pattern of fragility may be traced via a simple two-state bond model to a common variation of configurational entropy with connectivity. However, in order for this universality to appear the connectivity of the oxide networks must be defined in a progressive manner that accommodates the presence of those rigid structural units which comprise both the short range and intermediate range order.Replacement of these robust structural units by equivalent network nodes is necessary but can be viewed as a coarse-graining of the network to a bond lattice of weakest links that are most relevant to zero-frequency properties like the fragility.PACS# 61.43.Fs, 64.60.aq, 64.70.ph 2

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Erratum: Role of intermediate-range order in predicting the fragility of network-forming liquids near the rigidity transition [Phys. Rev. B 87, 054202 (2013)]At the time of publication, we were unaware of earlier work by Nemilov [1,2] whose early suggestion that fragility might be correlated with average bond connectivity is relevant to the topic of our paper.