Emotional and social filters, bending reality to take action

In one part of the experiment, there is a trolley coming down a track at full speed, further ahead, there are four unsuspecting workers engrossed in their daily tasks. 

On the side of the track there is a lever that could be pulled to divert the trolley onto another track on which there is only one worker.
When asked, almost all the participants in that experiment said they would pull the lever sacrificing one worker to save the life of four people.
The decision was rational and logical, sacrificing one life to save four lives, at least in theory.
The second part of the experiment involved again the same four workers and the same trolley, but this time Instead of a lever, we had another option. 

On an elevated platform overlooking the tracks, stood a stout man enjoying the view, and munching on the last bite of his lunch, with his arms folded across his chest.
To stop the train, we would need to push him off the platform and onto the tracks. His weight would be able to stop the train and save the four workers.
The result would be the same for both experiments, sacrificing one life to save four lives.
This time, none of the participants agreed to push the man onto the tracks, it caused them an ethical dilemma.
Pulling the lever involves our reasoning brain, while pushing the man off the platform involves the emotional part of the brain, because we are directly involved in the action, there is no "cushion" between our action and our ethical mind.

These "cushions", layer or filters come in all shapes and forms. A filter could be reducing humans to the level of animals which would make it easier to harm them, it could be pulling a trigger as opposed to chocking a man while looking directly into his eyes and imagining his orphan "to be" kids.

When these artificial layers and filters exist between us and and our decisions, it becomes easier for us to take actions, the thought of which alone, would make shudder in "layerless" situations.