Extremum principles are abundant in theoretical physics. In this talk I will consider Gibbs’ principle of maximum entropy in particular, and compare this to the principle of virtual work and the principle of least action. 

I will focus on two related issues: in what respect do such principles reflect a ‘tendency’ of Nature, or perhaps even some teleological goal? The second issue is the status of the ‘virtual’ variations involved in such principles. I will argue that these might be understood as a higher-order type of counterfactuals.