I recently realized how to get advice from anyone I want. It doesn't matter whether they are too busy to answer or can't because they are, I don't know, dead for a few hundred years.
If they've shared enough thoughts with the world, not even death can stop you from making them your mentor. (Well, yours can, but you probably won't need mentors when dead, so we are covered there.)
I noticed that whenever I spend enough time reading and listening to someone's thoughts, I start to understand how their mind works. I sense their values, tendencies, and reasoning. They materialize in my head. Suddenly, I can ask them questions, and I know what they would say.
So if you want someone you admire as your mentor, devour any thought they put into the world. Read their books, articles, and biographies, listen to podcasts and lectures. It takes time, but the reward is worth it.
After you know your heroes well enough, they'll answer all your questions. They become a council of mentors you can carry with yourself forever.
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