“ Political power can’t be share” this statement what views are given from long time period?

For a long time it was believed that all power of a government must reside in one person or group of persons located at one place. It was felt that if the power to decide is dispersed, it would not be possible to take quick decisions and to enforce them. But these notions have changed with the emergence of democracy. One basic principle of democracy is that people are the source of all political power.