On the Role of Theory in Biology

gist

Ulkar Aghayeva argues that theory in biology is generative of discovery, not only a summary of experiments, yet lacks physics' institutional standing. From genes and receptors to the genetic code and chemiosmotic theory, imagined entities and mechanisms often preceded lab confirmation. She traces theoretical biology's many branches, contrasts biology's mechanism-seeking epistemic culture with physics' law-seeking one, and points to sloppy models—few stiff parameters amid many disposable ones—as a shared route toward compressible biological theory.

ideas

• Theory often invents biological entities before experiment finds them. Aghayeva follows Jeremy Gunawardena in listing genes, receptors, enzymes, ion channels, and tumor suppressors as concepts postulated ahead of discovery, alongside mechanism theories such as the genetic code and chemiosmotic theory.
• Theoretical biology flourished as many fields but stayed institutionally scattered. Population genetics, systems biology, and related specialties grew beside experimental labs, while theoretical physics kept a distinct departmental identity and prestige.
• Biology's epistemic culture seeks context-dependent mechanisms more than universal laws. Cells and organisms carry developmental and evolutionary histories, so variation can be causally meaningful rather than noise around an ideal parameter.
• Sloppy models offer a path toward compressible biological theory. Only a few stiff parameter combinations drive observable behavior; many others can vary widely with little effect, which can coexist with evolutionary optimization and robustness.
• Physics-style renormalization does not cleanly transfer to living systems. Inhomogeneity and missing symmetries make coarse-graining harder in biology, even when low-dimensional predictive structure still appears for system-dependent reasons.

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