Why did gustave courbet start the 19 century art movement known as realism?

He wanted to represent subject matter trthfully avoiding artistic conventions and supernatural elements avenue wanted to represent things the way they really are

It depends on what type of third separates the three notes.for example: if you have two mayor thirds is an "aumented chord"if you have two minor thirds is an "diminued chord"if you have one mayor first and then one minor is a "mayor chord"and inverted is a "minor chord"