IMO they are on different dimensions, orthogonal if you will. The medium will often be dictated by outside demands, but when talking about mediums themselves an

IMO they are on different dimensions, orthogonal if you will. The medium will often be dictated by outside demands, but when talking about mediums themselves and the different aspects of that medium can take place without taking those into account. Just like you could discuss the differences between oil paints and acrylics without taking into account any specific work... of course if you flip that, talking acrylic or oil for a specific work, then it would matter.