Many philosophies are nervous of a realm of abstract entities, such as numbers and universals, as opposed to empirical objects and stuff located at places and times. Nominalism is the general programme of showing that mention of abstract objects is not what it appears to be, but a misleading way of talking about more ordinary objects. Friends of abstract objects say that there is nothing wrong with referring to them, but we must not make the mistake of imagining them to be especially large or spread-out kinds of concrete object. Another dispute concerns whether, when we do such things as see an edition of the morning paper, or admire a computer program, or hear a word, we literally see or hear abstract objects, which are therefore elements of our experience. See also Platonism, universals.