• The pessimist says "the glass is half-empty."
• The optimist says "the glass is half-full."
• The literalist says "the glass is completely full; half with water, half with air."
• The engineer says "the glass is twice as large as it needs to be."
• The mathematician says "the percentage of glass, by volume, that is filled with liquid can be approximated by the ratio one over two."
• The chemist says "the bottom half of the glass contains a hydrogen-oxygen substance which is a solid at STP and the top half contains a homogeneous, gaseous mixture consisting primarily of nitrogen and oxygen, with a few other compounds and elements."
• The statistician says "by randomly sampling the population, we can determine the mean, median, and standard deviation for percentage of the population that perceives the glass as half-full and by fitting a probability density function to the data, we could tell the probability that any randomly chosen person would see it as half-empty."
• The journalist says "Tragedy struck the world today, as civil war broke out between rival factions, at odds with each other about whether the glass is half empty or half full."
• The psychiatrist says "the way you view the liquid in the glass is evidence of your repressed sexual desires."
• The sociologist says "the way you perceive the glass is the by-product of class warfare within a society which unfairly treats women and minorities."