Can someone of you explain to me the problem of universals?

Basically it's the question of how there can be many things that are classified under one name, i.e. how are St. Bernards and Golden Retrievers both dogs but also distinct kinds of dogs.

>>2625628
I understand they both have their "dogness", and those are simple examples but for example the fatness, its a universal isnt it?
You cant imagine it on its own but you can clearly identify it in a person, isnt that contrary to the idea of universals?
Oh also i dont get that thing of "an individual cant be the predicate of something"

colors are the easiest way to think about universals imo. a lot of things are blue, but there's nothing that we could call "blueness"

>>2625714
(nothing unless you accept universals, i mean)

What i should have said is that i understand most of the idea, but there are some things like the concept of "categories" and "things that are said about other things" and "things that are inside things" that i dont understand.
Do you know any of that?
>>2625714

>>2625741
categories are just universals on a larger scale i think. so you have "dogness" and "animalness," etc. categories get larger and larger, so it's only natural to ask whether there's some largest category or if it's just an infinite chain, which is one of the problems people have with platonic realism

>>2625685

Whether or not one thinks that universals are just words, concepts, or real entities ( or have some intricate schema involving several of things so to explain it) is exactly what the problem is.

If you go the nominalist route ( they are only words) then you have to account for how our categorization isn't just constructed through our language, as opposed to having anything to do with reality.

If you go the conceptualist route ( universals are just ideas) you have to account for how these thought's match up with something real in the world.

If you are a realist ( you really believe that in some sense universals exist) you have to account for how these odd entities exist, and how it is that you can on one hand have something that is both just one unified thing while also existing in many different things at the same time.

The best account I can think of is Scotus's. Thing's are individual in reality, but they have a formal distinction in them ( a distinction that does not imply that they could actually exist separately, while still being objectively distinct from one another) between their "thisness" or individuality, and their "whatness" or their universal property. The "dogness" as an actual separable entity is something mentally constructed from the "whatness" we find in really existing things. It takes allot more to fully explain the theory, but this gives a brief sketch.

Avicenna also has a nice account, the essence or "dogness", for example, is neither universal nor individual when considered in itself - it has a third status distinct from those two. When instantiated in a concrete substance it is individual, when it is instantiated in thought it is a universal.

An individual cannot be a predicate as a matter of grammar. If we say, person x IS person y, we haven't predicated, we've made an identity claim. When you predicate you are saying something like " X is red" or "x is fat", that's just the way it works in language.