You can’t measure intelligence by how much you know, so don’t lament the fact that you only know a little. The answer to “how much do we know” is always “not nearly enough.” And so much of what we know is so specific, so situational. That cannot be the measure.
And you certainly can’t measure intelligence by how much you don’t know. Heaven help us if that were the measure! Just the amount of information that you know you don’t know is staggering, and imagine the orders of magnitude more that lie beyond that.
(Once, as a young child of around seven or eight, I told my father: “I think I know everything, because I can’t think of anything I don’t know.” His laughter was tremendous.)
So how then, can we measure – if measure we must? The same trusty measure that helps us in so many situations: rate of change.
Learn well and never stop. As long as the rate of change never hits zero, you’re doing okay. And you can always grab another book, attend another seminar, watch another video, have another conversation. Leave the gates open, and you’re as smart as you need to be.