Is intellectual validation a necessary motivator to you? I think you’re mostly correct about the vast majority of intellectuals. After taking my first philosophy course my senior year of high school at the local college, I had a romantic dream of getting my philosophy degree in Chicago and after graduation living a life of asceticism, working as a dishwasher by day and retiring to my studio apartment filled with books that I would spend the rest of my life studying to gain a godlike knowledge. I never attained such lofty ideals, and I would argue that this would actually have been MORE selfish than seeking intellectual validation. It may be somewhat selfish to seek validation, but the exchange of ideas is actually necessary to the functioning of a healthy community.
It turned out that I do want validation, but I also want to learn from others. The moral thing to do (which I must admit isn’t always easy) is to share your ideas humbly and take criticism constructively. This is the ideal that I and most people I have encountered fail so miserably at on a daily basis.