Philosophy does not make things complex.

Things are complicated themselves, philosophy just make you to think about all the implications.

Is it OK to push the fat guy? To me, it depends on the perspective. If I am just an onlooker, I won't push the guy, as I am not responsible for otherwise killing the 5. Killing one person vs. not saving 5 persons have greatly different psychological effect on me. But if I am the driver of the trolley car and I have the option of turning the steering to open a trap door to drop the fat guy, yeah, I will do it. For the driver, the options are killing one or killing five, while for the onlooker, the options are killing one or not saving five. There is a huge psychological distinction.

Is it OK to kill the cabin boy? No, I won't do it, but I am OK with lottery idea.