Are Economists selfish and rational?

Some fear that it might undermine social cohesion and the level of cooperativeness in our societies, if school or tertiary education increasingly confronts young people with the homo oeconomicus actor-concept as a basic analytical tool in economics and modern social science in general.
In his paper "Are Economists Selfish and Rational? And if so, Why?" (pdf), Simon Niklas Hellmich discusses survey and experimental evidence that has been collected to examine whether people trained in economics are different with respect to their preferences and behaviour and whether this could be a result of their education.
This evidence, Hellmich argues, is unfortunately inconclusive. Future research could benefit from replacing dichotomic constructions used to describe and interpret empirical findings with more recent actor concepts as suggested in psychology, economics, and sociology.