This work argues that the behaviour of living organisms cannot be reduced to physio-chemical causality. Suggesting that molecular biology is now at the same point as Newtonian physics on the eve of the quantum revolution, the study promotes a theoretical biology heralding a natural philosophy of organic life. Explicitly repudiating "vitalism" (the notion that the laws of nature need to be modified when applied to living organisms), the author argues that the structural complexity of even a single living cell is "transcomputational" - that is, beyond the power of any imaginable system to compute. Beginning from this premise, he leads the reader through a step-by-step process which ultimately arrives at the conclusion that living and non-living matter are separated by "a no-man's-land of irrationality". Elsasser concludes that an organism is a source of causal chains which cannot be traced beyond a terminal point because they are lost in the unfathomable complexity of the organism.