A causes B, and B causes A. A changing electric field generates a magnetic field. An electric field whose change is changing generates a changing magnetic field which itself generates an electric field. An electric field whose changing of change is changing generates a magnetic field whose change is changing which itself generates an changing electric field that generates a magnetic field. If this change is infinitely rough, this pattern extends endlessly. If A causes B, and B causes A, then is it possible for: -inf...... >> A >> B >> A >> B >> A >> B >> A >> B >> A >> B >> A >> ......+inf The only way the change can be infinitely rough is for the pathways of energies to be infinitely rough, which require infinetesimal forces and accelerations, and hence infinitesimal energies. The largest possible thing is something that cannot change, something that is not subject to acceleration, or a change in path - that would have to be infinity (non-object). Are all things in the universe caused by things that cause things like themselves?