Continuing our journey of 6 years of spreading worthy ideas from Tehran, we are fascinated with the effects of ideas. Yet we have so many challenges in front of us: climate change, our collective future, artificial intelligence, etc. Nothing is in our absolute control but one thing is certain: we need to act now! or we can not tell our children that we did our best. We, at TEDxTehran, believe that to take action, we need to inspire Responsible Optimism. For our next event, we are bringing optimists (both among speakers and audience) who believe they have the ability to influence the events of their lives and others also willing to take responsibility for their optimism and act on it. Hail to our friends at the HUS.Institute who gave us the inspiration to think about Responsible Optimism.