Final answer:
The Pauli exclusion principle, stated by Wolfgang Pauli, prohibits two electrons in the same atom from having the same set of quantum numbers, meaning they can't have the same quantum state.
Step-by-step explanation:
The Pauli exclusion principle hypothesized by Wolfgang Pauli, states that no two electrons in an atom can have the same set of quantum numbers.
This effectively means that two electrons cannot be in the same quantum state within an atom. The quantum numbers include the principal quantum number (n), angular momentum quantum number (l), magnetic quantum number (ml), and spin quantum number (ms). Therefore, according to the Pauli exclusion principle, two electrons in an atom cannot have the same values for all four quantum numbers simultaneously, which directly addresses the question at hand—electrons must have different quantum states to comply with this principle.