What is thoughtfulness? Why is thoughtfulness important? How do we become more thoughtful?

Thoughtfulness could be defined simply as "thinking about things". That's pretty vague, so let's define it a little more. Let's first look at the Webster Dictionary definition of the word "thoughtful"

Definition of THOUGHTFUL
1
a : absorbed in thought : meditative
b : characterized by careful reasoned thinking <a thoughtful essay>
2
a : having thoughts : heedful <became thoughtful about religion>
b : given to or chosen or made with heedful anticipation of the needs and wants of others <a kind and thoughtful friend>
— thought·ful·ly adverb
— thought·ful·ness noun

As we can see, being thoughtful is more than just having thoughts. Being thoughtful means that you don't just act impulsively or emotionally, but insteady you take time to think about the implications and the affects of any of your actions.