“Sir, we have as far as possible closed every avenue by which light may enter their
[The slaves’] minds; we have only to go one step farther,
—To extinguish the Capacity to see the light and our work would be completed”
This quote is expressing a scene of some soldiers who have some slaves in their prison the soldiers are telling to their head/commander that we have closed all the possible ways all the possible roads or tunnels and any other possible avenue through which they can even try or think to escape from here to get rid of this prison anytime or by having any chance in coming time/days. Now we just have to take one wisest and the best step to completely destroy their every hope every single prospect of them to escape from here to get rid of this hell if they have it. Then our work will be finished completely and clearly without any doubt and we would be relaxed ahead. After this one last important step we will be relaxed and get comfort with this.
Their commander/head responds by listening all their instructions that “we good my soldiers I am proud of your efforts and hard work I appreciate your loyalty towards your duty this is the sign of a successful person to do your tasks with loyalty and hardly . Now I will take the last step to completely destroy their every single hope of escaping from my prison I will show them that if they even think of escaping from here what will happen to them I will make them a weird lesson for others that no one will ever again try to escape from there and the last step is just enlighten every avenue’s entrance with fire and shower diesel on the gates so that if anyone try to pass it in sense of escaping he/she will get burned immediately. They will get a horrifying lesson that escaping through this hell is just impossible for them. They have to live here till their last breath.