Can you open your heart for a stranger?

I think most people will be afraid of getting hurt, being manipulated and taken advantage of. I believe a genuinely open hearted act can transform other person, even if they are bad. How they say, at the time of death, people repent for wrong doings, i know that there is a space in everyones concsiousness that knows as to what is right and wrong, in stark contrast of absolute goodness people eventually will realize their wrongful acts.
Some great person said " those who live for others they alone live". Somehow i can relate that one selfless act fills my heart more than all the things i supposedly do for me and my family. If only we can consider this whole earth as our big family. Smile at random person. Make someones day. We wudnt be so pathetic any more. I guess we are taught all wrong concepts of life.