Happy Birthday Yan,
I was 50 a few years ago but am still exploring what my fate will be. After retiring at 60 I found myself free of the life style needed between ages 18 and retirement for a formal education, to earn money to live, and to raise a family. After retirement there were so many new things to try and so many new doors to open it has felt like a huge rebirth.
I have never focused on life as a "mystery". But I will never forget those moments of feeling part of something much bigger than myself, a feeling of transcendence into a deep universal matrix of life and energy. It was a feeling of elation and connection to the beauty and interconnectedness of nature around me - the stars over the city lights of Helena, Montana; the sun shining thru the interwoven tree branches; the babbling brook running over rocks and thru the forest; walking in a wilderness of ferns as tall as I was as a child in Seattle. It inspired me to watch for new opportunities to experience deep connection with the "natural" world. It strengthened my commitment to expanding the health of nature around my home and within my community. It shaped my drive to build a feeling of vitality, safety and abundance within nature's nearby sanctuaries for me, my grandkids and my community. I have had some success within my Village of Northbrook creating community gardens, expanding bicycle facilities and now restoring a large section of the Chicago River. New personal experiences include fun with grandkids, singing, participating in political activities and participating in a weekly discussions of current events. Life is rich and full. Even as you pass 50.
Best wishes Yan.