Joshua Weitz

"Uncharacteristically for biology, s were very much part of the formative studies of that were designed and executed by luminaries such as , , and . Of these, Delbrück was a physicist, and papers from the early days of phage biology (certainly those with his name attached) reveal quantitative thinking that helped build intuition regarding the dynamics that could be seen at scales far larger than those at which the actual events were unfolding. These early studies provided the foundation for subsequent diversification of the study of phage: the basic concepts of what happens subsequent to infection, experimental protocols for inferring quantitative rates from time-series data, and methods for interpreting and disentangling alternative possibilities underlying the as-yet-unseen actions taking place at micro- and nanoscale (Delbrück 1946; Lwoff 1953)."

"Quantitative reasoning alone is critical but not sufficient. If it were, then the paradigm of mathematics and physics classes would seem to be a viable path forward for a parallel pedagogical track in the . That is to say, take a set of established equations, analyze them, explore the logical consequences of the relationships, and use their solutions as a proxy for the behavior of the natural world. However, unlike the constitutive equations of physics, a mathematical set of equations that describes a living system is not necessarily a hallowed object—not yet, at least. Models of living systems should not be put on pedestals nor conflated as substitutes for measurement. Models, mechanisms, and their predictions must engage with evidence taken from living systems in an iterative fashion—with far greater frequency than in certain branches of physics."

". The word may seem an unlikely start for a book meant to explain the . Yet, over time, we have learned that nearly everyone who was infected with survived—roughly 99% (or more). Not only did the vast majority survive, but many—if not half of those infected—had such mild infections that they never knew they had the virus. They were asymptomatic."

"We have to follow the . The data doesn't follow our narrative."