Analog carries the trace of a hand; digital carries the precision of a system. It is usually the first thing a viewer clocks about how something was made. Post-Modernism leans digital, Impressionism stays closer to analog.
Organic feels grown; geometric feels drawn. It is the difference between a form that occurred and one that was decided. Post-Modernism leans geometric, Impressionism stays closer to organic.
Minimal asks the eye to rest; maximal asks it to keep looking. At this distance the two want different amounts of the page. Post-Modernism leans maximal, Impressionism stays closer to minimal.
Futuristic points forward; nostalgic points to a specific remembered moment. One promises what is next, the other that something familiar is still true. Impressionism leans nostalgic, Post-Modernism stays closer to futuristic.
Impressionism vs Post-Modernism: 78% affinity (Highly compatible)
Where they split: Post-Modernism leans digital, Impressionism stays closer to analog. Also diverging: Organic vs Geometric (40% gap), Minimal vs Maximal (30% gap), Futuristic vs Nostalgic (25% gap). Where they agree: both lean expressive.
Safe to blend: close enough that mixing Impressionism and Post-Modernism reads as one coherent direction, not two competing ones.