In an interview with World Magazine‘s Megan Basham, Stanton explained his singular vision for WALL-E:

What really interested me was the idea of the most human thing in the universe being a machine because it has more interest in finding out what the point of living is than actual people. The greatest commandment Christ gives us is to love, but that’s not always our priority. So, I came up with this premise that could demonstrate what I was trying to say—that irrational love defeats the world’s programming. You’ve got these two robots that are trying to go above their basest directives, literally their programming, to experience love.^[17]

from Wikipedia