So ancient humans in antiquity from the evolution from apes to human had always tried there very best to survive, its like the only thing that they where concerned about since we where animals and all animals care about is survival of their genes proxy to there own survival. We after ( I’m guessing) the agricultural revolution have secured our place in earth like now we have seriously got it we won against the animal , now that became our problem we had been animals for longer that we have been humans a part of ourself is part animal we are creature of survival. Now we can’t turn off that part of our brain which is built for war . In conclusion we have won the war against other animals but by doing that we have no other choice but to turn our deadly gaze to other and then if we can’t then we will turn the gaze inward (our conscious) thats what giving the feeling of meaninglessness in our life .