Was there a "magic moment" when truly human beings first appeared?

No. I was just using consciousness in the sense others used it for a human state of awareness.

Maybe it is better to say words and thoughts are pretty tightly coupled. Words are the abstraction, the ability to assign specific objects and actions into categories. I doubt language would have arisen if humans lived solitary lives. Humans are not equipped with much in the way of speed, strength, or other survival gear; socially based coordination and complexity is the strategy, and the rest is history. So in regards to the “magic moment” when truly human beings first appeared, I am inclined that the first French speaker discussion is more than an analog here. If that were a discrete, instantaneous moment, it would have had to be so in a very limited, very very arbitrary sense.