What does "the path of least resistance" really mean? A lot of physical phenomena tend to be explained (at least on a superficial level) by referring a current or particle flow's tendency for it's trajectory to follow the "path of least resistance". I've always found this explanation peculiar. How does a particle or electron "know" or have forewarning that surrounding adjacent paths are more resistive and that it should not venture down them? For simple conductors this seems obvious. The conductor is filled with charge carriers, so as soon as a potential is applied across it, the potential gradient distributes itself across the length of the conductor and the electrons lose energy in all points simultaneously in the conductor. If multiple conductors are in parallel then current flows through all conductors at different rates proportional to the conductivity of each conductors. A very similar scenario applies to water in parallel pipes. This got me thinking about electrical discharges and breakdown in a gaseous dielectric. How can these discharges follow a path of least resistance? Surely a local fluctuation (or the presence of impurities) which results in the resistivity of the dielectric being lowered locally can only be exploited if the path of ionization happens to wander through it. I can't reconcile this with the explanation I've been given that "lightning follows the path of least resistance". Imagine an experiment featuring a sharp high voltage cathode suspended above an infinite plate which is grounded. The cathode is subjected to many thousands of voltage impulses and the results are recorded using a triggered camera. One would expect that when all of the images are overlayed, the result would be a purple discharge cone that is darkest in the centre (the shortest path between the electrode and plate) and symmetrically becomes less dark towards its edges (let's ignore the fact that because we're imaging a 3d cone in a 2d plane the centre is going to be darker anyway. pretend we've digitally removed that effect). I have done some reading into gaseous ionization processes involved in avalanche (fast) breakdowns (i.e. not coronas). As far as I can tell, the electric field distribution within the gas doesn't seem to affect the probability of charge carriers being produced. Now imagine that a length of conductor is (isolated and) suspended in the discharge area outside of the cone such that it provides a path of relatively low resistance but is in an area where it is statistically unlikely that the ionization random walk processes are going to encounter it. Will the current somehow find its way to this piece of conductor? Will it induce an electric field locally within the gas which causes charge carriers to be attracted to it? Do lightning towers actually actively attract stepped leaders, or do they guide lightning discharges simply by providing a path for upward positive leaders to meet with downward negative leaders? Sorry, I know it's a bit hard to isolate a single question in this post. I'm just after a general discussion on the topic to shed some light on it.