@gondwanalon, many parents have observed that before a child is two-years-old they will act on their impulse to take something they want that another child is holding. However, when the other child picks up another this object it becomes desirable and it is taken away. When the empty-handed child picks up the original object that has been discarded, this again become desired and is taken away.
By this point, an adult will intervene and admonish the offending child. Though it is unlikely that this lesson is accessible to a four-year-old, the emotional link between taking what is not theirs and the disapproval that can result should an adult know about it has been established. I doubt that as a four-year-old you experienced guilt, but it is likely that you felt the fear of rejection and it was sufficient to inhibit acting on this impulse again.
There is a difference between the mental capabilities of an adult dog and an adult human, but not between a dog and a very young child. People have the capacity to learn how to relate to a more complex reality. We have the ability for language, symbols that enhance access to memories and conceive of future possibilities. Abstract thinking is unlikely to exist in other animals, but is a necessity for our cognitive power. In this way, ” humans can see the bigger picture and have the ability to rise above the past. We can choose to let the past all go and think positive and hopeful towards the future if we want to.” However, a young child has not develop the intellectual skills necessary to make the kind of choice you posit.