Roman R. Poznanski discusses the new book that he co-authored, Mathematical Neuroscience. In the second decade of the twenty-first century, brain researchers (neuroscientists) have begun to decipher the dynamics of large-scale neural networks and to gauge how the functioning of the brain is dependent on the spatiotemporal integration of the resultant dynamics. Knowing more detailed facts about brain connectivity, we are faced with the problem of how such information can be put together in one system to understand the whole brain and the effective tracing of cause-and-effect relationships determining its actions. Data gathering by neuroinformaticians steadfastly produces a ‘brain in a supercomputer’ virtual model that can be regularly updated to fill in the missing pieces of the puzzle. Unfortunately, such data gathering does not imply that there is a “glue” that allows us to join together multiple empirical observations into a complete theory of the brain.