Complexity in biology. Exceeding the limits of reductionism and determinism using complexity theory.

the ultimate aim of scientific research is to understand the natural world. in order to achieve this goal, Western science has relied on different cognitive strategies, including simplification, both in terms of analysis and explanation. as the British natural philosopher Sir isaac Newton (1643–1727) put it, “truth is ever to be found in the simplicity, and not in the multi­ plicity and confusion of things.” in a way, examples of simplification include using idealized models, such as a ‘perfect sphere rolling down a smooth plane in a vacuum’; conducting experiments in a strictly con­ trolled environment such as the laboratory; analysing complex systems by reducing them to their individual parts; and generally by using a linear and deterministic concept of how the world, including life, works. the French philosopher and mathemati­ cian rené Descartes (1596–1650) was the first to introduce reductionism to Western thinking and philosophy. according to his view, the world can be regarded as a clock­ work mechanism; to understand it, one need only investigate the parts and then reassem­ ble each component to recreate the whole. Descartes’ work was expanded by Newton (1643–1727) and ultimately culminated in the Principia Mathematica in 1687—one of the most influential science books ever writ­ ten—in which Newton further advanced the idea of a ‘clockwork universe’. Since the time of Newton, classical mechanics has been regarded as the founda­ tion of scientific research. Scientists, includ­ ing biologists, have adopted the Newtonian approach both at the ontological level—in terms of their conception of the world and the things of which it is made—and the epistemological level—in terms of their approach to understanding those things. the Newtonian epistemology, in fact, states that scientific knowledge has to provide an objec­ tive representation of the external world. the world’s apparent complexity can be resolved by analysis and reducing phenomena to their simplest components. “Once you have done that, [the evolution of phenomena] will turn out to be perfectly regular, revers­ ible and predictable, while the knowledge you gained will merely be a reflection of that pre­existing order” (Heylighen et al, 2007). Ever since Newton formulated the first laws of gravity, the conceptual model of the physical world had successfully described the shape, movements and actions of the objects within it. But as physicists began to explore especially the atomic and sub­ atomic realms in the early twentieth cen­ tury, their observations became partially meaningless. the new discoveries required a paradigm shift and a new intellectual framework to understand events at the sub­ atomic level, which eventually resulted in quantum physics.