Comments and authors' reply on "Linear stress-strain relations in nonlinear elasticity" by A. Chiskis and R. Parnes, (Acta Mech. 146, 109-113, 2001)

Recently this journal published a work stating that the idea of geometrical nonlinearity within Hooke's law is "no more than a widely accepted illusion since the linear stress-strain laws hold only for very nontrivial measures representing the corresponding strain tensor which depend on material parameters". Since the linear stress-strain relations with nonlinear strains are, indeed, widely used in research and design the arguments of the authors of this work should be considered. Below it is shown where a flaw in these arguments is and why Hooke's law with nonlinear strains is correct.