Is knowledge power?

I used to think that knowledge was power, that it could be wielded like a weapon, or built up like a wall, then used to justify the limits and boundaries of any given group. If you possessed certain knowledge you were ‘in’ and if not you were ‘out’ – an elitist U and non-U, but for the brain rather than societal manners. The effect, in any case, is the same, which is to consolidate a hierarchy of dominance. And you feel it the more keenly when you are on the receiving end of the power kick that is knowledge: when knowledge is used against you, to keep you in your box or deny you access to realms you might want access to, to belittle you, shame you,