The weird connections between things

or why life is counter-intuitive: this story (in the New York Times [link] ) indicates that bacterial and parasite infection (common in the "native" state of humans, but increasingly rare in modern, "hygenic" societies) helps modulate our immune and inflammatory systems.  

In a world where we are shielded from such chronic infections, we are more sensitive to "out of control" inflammatory responses, which in turn lead to diseases as asthma and autism.   In a weird way, being sick (or infected) keeps us from getting sick.  

Teaching the young (and old).

Studies on brain development development indicate the people's brains continue to change through their 20s.  Moreover, it is worth remembering that the very process of learning (rather than remembering) takes time and practice.

It is possible to remember, quite vividly, one time events, but mastering hard ideas, skills, etc., takes repetition.   (One reason sports teams and athletes practice so much!)