Elie Metchnikoff

The appearance of aged persons is too well known to make detailed description necessary. The skin of the face is dry and wrinkled and generally pale. The hairs on the head and the body are white. The back is bent, and the gait is slow and laborious, whilst the memory is weak. Such are the most familiar traits of old age.

Astonishingly, in spite of decades of research, there is no agreed theory of cancer, no explanation for why, inside almost all healthy cells, there lurks a highly efficient cancer subroutine that can be activated by a variety of agents - radiation, chemicals, inflammation and infection.