Why doesn't polymorphism work without pointers/references?

Question

I did find some questions already on SO with similar title- but when I read the answers they were focussing on different parts of the question which were really specific (e.

Answer 1

You need pointers or reference because for the kind of polymorphism you are interested in (*), you need that the dynamic type could be different from the static type, in other words that the true type of the object is different than the declared type. In C++ that happens only with pointers or references.

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(*) Genericity, the type of polymorphism provided by templates, doesn't need pointers nor references.