Each of us has a rich inner mental life, one that seems inaccessible to everyone else. To others, we believe, we represent a kind of human terra incognita. After all, how can anybody really know what is on our mind?

As it turns out, however, our feelings and thoughts are only too visible to those who know how to look. You will learn why in our special report, “The Body Speaks.” Tiny “microexpressions” involuntarily flit across our face, revealing our emotions, as Siri Schubert explains in “A Look Tells All,” starting on page 26. In “Gestures Offer Insight,” beginning on page 20, Ipke Wachsmuth describes how we make hand or other motions to add shades of meaning to words as we converse. And when we fib, our very physiology can give us away, Thomas Metzinger details in “Exposing Lies”; go to page 32.

Getting an outside vantage point also helps us find other things that can seem hidden or unavailable: novel ideas. Basic knowledge of a given field helps, of course, in the quest for a problem’s solution. But simply proceeding step-by-step like a computer will get you only so far. To summon those priceless flashes of insight takes a new point of view. “The Eureka Moment,” by Guenther Knoblich and Michael Oellinger, tells why on page 38.

Shifting perspective again, we recognize the value of insider knowledge and experience for sorting good ideas from bad in pop psychology. We may wonder, does a given therapy work as advertised? How is the average person to know what to trust? Now we are pleased to offer help: “Facts and Fictions in Mental Health,” a new column by psychologists Hal Arkowitz and Scott O. Lilienfeld. First up: self-help books. Do they really help? Flip to page 78 to get their take.

What’s your perspective on this issue’s offerings? We’d like to know.