Hi, I'm 19, and have been playing bass for just under 2 years now. When I first started to play, I knew so little about jazz theory that my goal was to learn all about chords, scales and so on. When I had a fairly good grasp of harmony, and a decent control of the bass, my aim was to write good walking basslines, and play them so they sounded good to me. My next goal was to be able to pick up a leadsheet to a tune and fake my way through (basslines, not soloing). After a whole lot of practice, I eventually got that down pat. When I read the posts on these forums, I can see most people advocate for "playing what you hear" - I completely agree with this, but it's much easier said than done. I've spent so much of my practice time learning how to "play what I see", that when I put down the leadsheet (even to a tune I know quite well), I can stumble through some of it, but I'll eventually forget one of the chords and it'll throw me off. I've devoted much of my time now to learning tunes without the lead sheet in front of me, but the problem is I'm still not playing by ear. I am STILL learning tunes by remembering where my fingers go on the bass and following the root around. While I'm not playing with any sheet in front of me, I still feel as though I'm not "hearing" before I play, but just playing what I know is right. I want to ask you guys: how do you really learn to internalise a tune's harmony? How can I learn to play a bassline without thinking of symbols or numbers... When guys say that they only play what they hear, how do they learn to to actually hear their own basslines in the first place? Thanks a lot in advance, Mike. By the way, I did have a teacher, but I've just moved interstate. There's only one bass teacher in the city that I'm aware of (Eric Ajaye). It may be a couple of months before I start studying with him, and I can't wait till then to start my new journey!