Derivative or not

Juan Gris- Glass and Bottle, 1913
Braque- Guitar- summer 1918
I have been thinking a lot about a question that I have to  answer for Nancy Crow's master class, and it is one I have puzzled about personally for a long time. Influenced by. Derived from. Copied. All very different in my mind. In the journey to answer this question I have spent a lot of time looking at the drawing collection at Moma - a collection that I have loved wandering through from time to time- as a source of inspiration.
Faced with the questions posed by Nancy I looked at the collection with a different eye- looking at similarities- where one artist might have been influenced by another- or where an era or style created similarities in approach. As part of my preparation I want to look at different groupings and see where an approach has been influenced by, derived from, or copied. Not having an art history background will make this merely conjecture, but it is fascinating to see where there are similarities and differences. Looking at the artists and the dates they created some of these pieces makes me think about the concept of originality and how these artists may have influenced each other in their use of color and shape. And while Franz Kline has a completely different approach and aesthetic I can not help but feel that he studied the collage artists of the early 20th century.
Braque- Still Life with Tenora- summer 1913

Kurt Schwitters- Drawing A2- 1918
Franz Kline- 1952