"What lies behind us and what lies before us are tiny matters compared to what lies within us." Ralph Waldo Emerson
You were curious as a child. That's how you learned what you know and how you associate yourself with the world and navigate through the physical universe, manipulating the ins and outs to suit your needs but hardly anything about the world inside you, that strangeness beyond form and the physical.
Unfortunately, as we age we lose that curiosity and exchange it for 'pretending to know.' We become complacent, smug, and very very dull. We become robotic, automatic and habitual and never changing, often saying stupid things like; "I already know that! Don't tell me! I did that! I saw that! I was there! I know!
Don't worry, if you've lost your curiosity, there are steps to regain it. Experiment a little, change your looks, your habits. Take a look at things from another perspective. Move. In other words get off your ass and go back to school or just read a book. Dissect, assemble and scramble. Pay attention to time and to your emotions.
Newton's law of motion may apply here; An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
I think he was on to something here, other than gravity! How about it? Have you lost your curiosity? Then stop pretending you know it all and get back to being curious, again!