So he does not expect the politicians that are representing himself to have principles either. Politicians realise this and notice that the only way they can get into parliament is if they represent the majority. They cannot get into parliament easily if they stand up for a philosophy. So the politicians must represent the majority but at the same time try to follow their political ideology. We end up with a system that suffocates principles and completely obliterates philosophy.
Politicians compromise their principles so they can get into power.
Almost all politicians do this and that is why democracy has no hope for the future. By comprising their principles they are following the average 'joe', who certainly does not have the answers. Compromising principles, or in most cases having none leads to many pointless debates. So we get pathetic arguments like focusing on how much welfare should be spent rather than whether compulsorily taxing people to pay for welfare is right. In a system like this we have no chance of ever finding the right code of morals used to govern society and no chance of having a stable government.