I was talking to a coworker about this. She is 26 and I said &quot;you honestly don&#x27;t change, like ever.&quot;<p>Granted, I skipped the part about changes that are surprising, but mentally, we are who we are and that feeling of youth never really left me (nearing 40).<p>I think that there is only two phases. The day you stop reinventing yourself and exploring possibilities, allow yourself to live in a rut, spend more time in front of a TV than out exploring the constantly changing world, and have nothing to show for the past year&#x27;s effort but a beer belly, is the day you die. I wonder if that is what was meant by adulthood at one time in the past.<p>As for feeling &quot;younger&quot; than younger people, well, I&#x27;ve always been sort of an old soul, but I think most people would consider my somewhat childish because I don&#x27;t think about or talk about my experiences too much. I try to live in the moment and don&#x27;t feel like I should share some aged wisdom. Life is more interesting and insightful with laughter, IMO.