do i

As I was reading a parenting book this weekend, I came across this statement included in their beliefs about children. 

"We maintain that almost everything children do is an attempt to learn and that there is always a healthy impulse behind a child's behavior." (pg. xxi Becoming the Parent You Want To Be, emphasis mine)

I've been thinking about it all weekend and whether I believe it.  I think I believe it in the obvious times.  The putting together a puzzle or stacking rings times.  The tasting new food and trying to sign times.  But do I believe it in the whining, grabbing at my legs times? The tantrum on the floor time?  (side note: why is it called a temper tantrum?  isn't calling it that saying it's a part of their personality? a flaw? and not a response to frustration and learning and growing?)

what do you think?  do those ugly, hard kid moments have an element of learning behind them?  and if so, what should my response be in those times?