Why the difference ? why are humans more disturbed by parasitism than predation?

It's the difference between killing something and using it as a host. If you kill something, great, it's done with, nothing more to it. If you use it as a host, as in parasitism, it will get sick and often exist as nothing more than a shell, keeping the parasite alive. Furthermore, when people think of parasitism, I think they think of leaches... which are gross.


Building on that, I think we relate these to our own experiences. Because most of use eat meat, killing for food seems natural. Furthermore, we tend to be the hunters -- not the hunted -- so, psychologically, we have no empathy for the animals being eaten. On the other hand, we're not used to parasites.