Peg writes:
Yes we have an instinct to eat, But some people will choose not to eat when hungry...anorexics are one example...people on hunger strikes are another. This shows that humans are not BOUND by instinct in the way other animals are.
Actually, when I was little our family ran into a situation where we had to give up our family dog. We gave the dog to someone we trusted. A few months later, we got the news that the dog literally starved himself to death.
Along the same line, a few months ago my wife and I had to go out of state for a family emergency. We put our 3 dogs in one of those dog care centers (they charged us extra for last minute drop off!). When we came back, we found out from the workers there that one of our dogs refused to eat. We were very glad to have gotten back in time. The incidence reminded me of our family dog years ago.