"Humans act. Action necessarily entails a goal. Having a goal entails preferring certain states of the world over other states of the world. Therefore, humans have preferences."

This looks like mere word-play. What is a goal? The thing you prefer. What is a preference? Your attitude to a goal. Can you restate your explanation, while tabooing "prefer" and "goal"? I could, for my understandings of those words, but it wouldn't necessarily come out meaning what you mean.