Fig. 1. Schematic representation of genotype-phenotype transformation from one generation to the next.

G and P are the spaces of the genotypic and phenotypic description. G₁, G′₁, G₂, and G′₂ are genotypic descriptions at various points in time within successive generations. P₁, P′₁, P₂, and P′₂ are phenotypic descriptions. T₁, and T₃ are laws of transformation from genotype to phenotype and back, respectively, during development. T₂ are laws of population biology, and T₄ are laws of Mendel and Morgan about gamete formation. Necessary and unnecessary complexities and molecular redundancy are defined in the text. (After Lewontin¹⁹). The graph lines are not intended to mean monotonic increase.