Why did kramer call the devolopment of writing sumer's most significant contribution to civilization?

Kramer regarded the development of writing as Sumer's most significant contribution to civilization because it revolutionized communication and record-keeping, enabling the preservation of information across generations. Writing facilitated the administration of complex societies, allowing for the documentation of laws, trade transactions, and cultural narratives. This innovation laid the groundwork for advancements in literature, education, and governance, ultimately shaping the course of human history.