Here's why:

* The Sun is a Star: The sun is a star itself, not a collection of dead stars. It's a massive ball of hot gas, primarily hydrogen and helium, that generates energy through nuclear fusion.

* Stellar Evolution: Stars go through a life cycle, and they die in different ways depending on their size. Some stars become white dwarfs, neutron stars, or black holes. However, the sun is a relatively small star and is expected to become a white dwarf after it runs out of fuel, not a collection of dead stars.

* Formation of Stars: Stars form from massive clouds of gas and dust called nebulae. The sun formed from a nebula around 4.6 billion years ago.

In short: The sun is a star that formed from a nebula and is not made up of the remains of other stars.