This beautiful little book was based on a sequence of popular lectures given in Dublin during WWII, and in turn on an earlier paper given in Vienna. In the book Schrödinger coins the idea of a genetic code carried by linear molecules with his phrase 'code-script'. He asks how, in the absence of validity of a large n limit required by statistical physics for the validity of any macroscopic biological laws, can the chromsome molecules that carry the code-script yield stable genetic rules. Then, he gives the answer: chemical bonding as predicted by quantum theory ala Heitler-London (Schrödinger identifies quantum jumps in the chrosomes as the origin of mutations, which are also discrete). He refers to the chromosome fibers as linear 'aperiodic crystals' (to emphase their stability in the face of thermal fluctuations) and encourages physicists to study them: he boldly asserts that both the instructions and mechanism for generating organisms via molecular replication are contained in the chromosome molecules (and there is where the "complexity" lies). This book encouraged physicists to study problems of complexity long before the term complexity had become the catchword that it is today. Indeed, our first ideas of 'complexity' were developed parallel in the same era by Turing and von Neumann.
Schrödinger is buried in Alpbach (Tirol), where he lectured and enjoyed the Alps frequently after WWII in a school organized by one of two brothers who, according to a very well-informed source, formed nearly the only Resistance in Austria during the war. On his grave is a pretty little plaque bearing the Schrödinger equation.
This review refers to the 1969 edition of 'What is Life'.