Why are there so many sayings and thoughts?

Probably because everybody has their own opinions and no two people can be identical in this respect. This diversity is the main cause of so many different ideas and sayings and questions and solutions. Thoughts are generated by your outlook towards something. Since, you cannot examine things exactly how others can, you have your own thoughts, and they have their own. Differences exist and they are extremely important. Otherwise, we are nothing but robots made out of blood and flesh.