Searching engines

Information from these engines do not make us feel dumber. However, Wikipedia for example, technically, they are not encyclopedia. Since all people in the world can easily access and upload or even add information into it easily as they want. How can this so-called 'encyclopedia' to be validate?   In my opinion, Wikipedia references are not so reliable as well. Since web user have no idea to find out where the sources are true or not, even students use Wikipedia for sources, it will lower the standard of solidity for academic writings. This is alos why Wikipedia wasn't a good web site and search engine by most of the professors nowadays.