How do you show that you care?

Would it be excuse enough to say that I don't know how? 
Or would no excuse be allowed?
How do you grasp a concept that is so immaterial?
One can only try. 

It leaves me lost to not know. 
What can I do?
I don't want to give up. 
Keeping silent seems safe. 
But it wasn't what was needed. 
Yet, what, then, is needed?

Am I simply an idiot not to know?