In the 15th century science began to develop and become more sophisticated. The term "renaissance man" means that people were not just specialized in on field, but they knew a lot about many different areas. They were not just Jacks of all trades, but masters of all trades.
Science was a major contributor to the change in art. Many of the paintings began to be more technically correct. There were more attempts at vanishing points, foreshortening, and different angles. They began to measure and realize that the further away something was from your eye the smaller it was. These mathematical approaches lead to better art over all.
There were burnings of many works of art that were considered heretical or sacrilegious. The Medici family were patrons of many of these art works. So the Medici family was driven out of their home until things blew over. This "Burning of the Vanities" was brought to an end when its leader Giralamo Savonarola was killed for being a heretic.
Today we have computers so everyone is making art whether or not they have had any sort of background in art. Everything is so much easier to measure and most of the work is done for you. Humanism doesn't have such an obvious role as burnings of pagan gods, but there are still some groups that would do away with certain types of art. There is still a big drive for individuality and fewer religious paintings that more or less look the same.