Our lives are full of boundaries.
Most inner and outer boundaries are born out of anxiety.
All anxieties emerge from differentials, causing powerful emotional dynamics (and momentum) in human actions.
Those differentials are always located in both,
in our FUTURE (expectation),
and in our PAST (imprinting).
If you multiply this by our present flow-gradient of mind, you get pretty close to what we call emotion.
Our past defines our now and our future.
Especially when it comes to boundaries versus openness.