Robots ask 'What is life?" and synthetic bacteria

Humans are nothing but machines. Our "sadness" has a number associated with it... biochemicals. Robots can solve problems, and robots can behave intelligently. Robots' "sadness" is also just a number. Why should their "sadness" be lesser, say, when you turn them off? In fact, humans have created a synthetic bacteria. And it's "alive" alright.

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