I believe they can feel either stressed and fearful, or secure and content. Whether it's towards their enviroment or keeper. They strive to find a secure setting, and strive to find food because they are basing their actions on their instincts.
I still believe this. Your experiences have made up your mind. I still believe they do not have the reasoning skills like mammals and higher animals. And yes, I believe your viewing basic instinctive actions as a reasoned self conscious thought.
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If you want to view a snake's being secure around you as affection, that's fine. But I think your pushing qualifications on them they aren't readily deserving of.