Complex sentence: Seth dreads the future and allows his memories of childhood to dominate his thoughts, but recognizes and criticizes his own obsessions: There's something in the decay of old things that provokes an evocative sadness for the vanished past.
Split into simpler sentences: Seth dreads the future and allows his memories of childhood to dominate his thoughts. Seth recognizes and criticizes his obsessions There's something in the decay of old things that provokes an evocative sadness for the vanished past.