The concept of mental health formation. It is the opposite of the concept of stress diathesis and is related to the notion of biological sensitivity to context (Boyce and Ellis, 2005). The basic idea is that people are not just different in their susceptibility and vulnerability to the negative effects of adverse experiences, but are plastic in their development. More “plastic” or malleable people are more susceptible than others to environmental influences, both for the worse and for the better, i.e., they are subject to both adverse developmental effects associated with a negative environment and more positive consequences with a supportive environment. On the contrary, less susceptible individuals are less susceptible to the influence of environmental conditions, regardless of whether they support or worsen them.