If our eyes only saw frames (IE: 30 images a second), like a single lens reflex camera, we'd see images pop in and out of existance and that would really be annoying and not as advantagous to us in our three dimensional space and bodies.
In the Vienna of the second half of the 18th century, in addition to Haydn and Mozart, three symphonic composers, namely Leopold Hoffmann, Carl Ditters von Dittersdorf and J.B. Vanhal helped further the development of the symphony.
The opera sinfonia, or Italian overture had, by the 18th century, a standard structure of three contrasting movements: fast, slow, fast and dance-like. It is this form that is often considered as the direct forerunner of the orchestral symphony.ozart 's early symphonies are in this layout. The early three-movement form was eventually replaced by a four-movement layout, through the addition of an additional middle movement (Prout 1895, 249), which was dominant in the latter part of the 18th century and most of the 19th century.