Abstract The statement that we are currently failing to address some of humanity’s greatest challenges seems uncontroversial—we not doing enough limit global warming a maximum 2 °C and exposing vulnerable people preventable diseases when produce herd immunity. But what singles out such failings (inactions) from all the things did do (non-actions) unintended? Unlike their individualist counterpa...

In this paper, applying two theorems of Ricceri and Bonanno, we will establish the existence of three weak solutions for a quasilinear elliptic system. Indeed, we will assign a differentiable nonlinear operator to a differential equation system such that the critical points of this operator are weak solutions of the system. In this paper, applying two theorems of R...