Jean-Jacques Rousseau (1712–1778), in his influential 1762 treatise The Social Contract, outlined a different version of social contract theory, as the foundations of political rights based on unlimited popular sovereignty.
The elements in the same column will have similar properties. Beryllium is the group II element. Group II elements are magnesium, calcium, strontium, barium and radium. Hence, these show the similar prperties.