More math vs. science. Mathematical objects don't exist in the way the physical objects exist, but you can study mathematical objects, and doing so turns out to help you understand the world. Think of Plato's forms as being like mathematical objects. Plato thought that spheres and rectangles were more real than the Earth and the page you're reading, which sounds a little weird with 2000 years of progress between us and him; we think of applied math as modelling real things, rather than real things being shadows cast by math. He had it backwards from our perspective, but we have the benefit of 2000 years of figuring out the relationship between relationships between maps and territories, and he was mostly treading new ground.
Most mathematicians will tell you math is just a game you play with symbols and that we don't really mean it when we say "these exists an x such that...", but there are mathematical platonists. Probably the most well-known modern mathematical platonists was Gödel. I don't know of any who claim the kind of relationship exists between mathematical objects and physical objects Plato claimed existed between the forms and physical objects. I'm hardly an expert though, they may very well be out there somewhere.