My very basic understanding of black holes leaves me with a question about why black holes increase in size, or rather, why does the event horizon increase in size. As I understand it, a black hole is a large amount of mass condensed into a such a small space that the amount of gravity produced overwhelms light (and anything else). This, as far as I understand, means that If the mass increases then so does the amount of gravity. But, if gravity increases then surely the black hole would become more compact, i.e. smaller due to the extra "pull". I can see how adding stuff to something "should" make it larger. That appears common sense but the event horizon, as I understand it, isn't something that the mass is added to, it's added to the "stuff" inside the black hole, i.e. beyond the horizon.. Could someone help me with my understanding without throwing the swarzchild radius at me (or if you do, please explain in laymans terms). Regards Mark.