Lex understood. Let alone trying to reverse time, even talking about it seriously, as if it were a possibility, would attract the wrong kind of attention. The consequences of it were not measurable yet, but he believed that if kept talking about how it was possible given the right circumstances, he would get in trouble.
Lex did not know if what he said was accurate, or even possible. He only theorized based on his limited information. In this universe, the flow of time was an irrefutable constant, one that ruled all of reality. By that logic, if a being or entity stronger than this universe appeared, it should be possible for them to reverse time since they would be strong enough to resist the strength of this universe's laws. Or, instead, the universe would be destroyed.
