I hope you dont mind my suggestion but here goes,
Perception is a feeling, as well as a thought and usually comes from the gut, its a personal feeling about a situation.
Where as perspective is when we look at all angles to a situation.
I perceive the boy to be honest as I know this person,subjective.
Where as the shop assistant has no affinity with the boy so therefore has an objective view of this.
Maybe by using these two words you could look at the essay as one's perception as a gut instinct rather than a more logical view.
I have just searched on wikipeadia:
 Types of perception
Perception as Interpretation
For perspective well this is completely from a logical point.
We putting things into perspective we are analysing a situation to make it realistic,
perspective (plural perspectives)
A view, vista or outlook.
The appearance of depth in objects, especially as perceived using binocular vision.
The technique of representing three-dimensional objects on a two-dimensional surface.
The choice of a single point of view from which to sense, categorize,
I hope this helps,you most probably know all this but I would go for something possible about every day life this way it may not be so hard to write.