Complex sentence: Two main schools of thought emerged from human geography and one existing school (behavioural geography) flourished briefly and sought to counter the perceived tendency of quantitative geography to deal with humanity as a statistical phenomenon.
Split into simpler sentences: Two main schools of thought emerged from human geography and one existing school (behavioural geography) made brief comeback. Behavioural geography sought to counter the perceived tendency of quantitative geography to deal with humanity as a statistical phenomenon.