I think the basic misconception is to speak of the so-called "best” allocation of resources. What is the best? In common economics it is defined as what would be if we knew everything. Economists operate with the fictitious assumption that all the relevant data is known, but this is totally unrealistic. Nobody knows all the data. What we have is widely dispersed knowledge, which cannot be concentrated in one mind. To call the situation-which would use all the knowledge available-"optimal” is nonsense because it is by definition a non-achievable solution. Our problem is not the full utilization of all knowledge but the best use we can achieve with any known institutional structure. In that sense, some oligopolistic (and even monopolistic situations), represent the best possible utilization of knowledge that we can achieve. Even the action of a monopolist can be extremely beneficial.