One distinct example from "The Passing of Grandison" where we see that things are not always as they seem is with Grandison himself. Grandison appears to be happy and content, one who would never stray from his master. The reality is that he actually does escape upon his return, thereby fooling everyone with his appearance of complicity. He "passes" for being a content and loyal slave, while the reality of his actions speak to another condition.
Such an idea feeds into the idea that Grandison's owners "know" or "understand" the mind of the slave. There is a belief that owners get fully grasp the condition of the slave's thinking. In an almost arbitrarily reductive manner, slaves are seen as simplistic and monistic, incapable of complex actions or thoughts. When Dick finds that Grandison has not taken any money from him even though he was afforded the opportunity to do so, Dick surmises that Grandison "... sensibly recognized his true place in the economy of civilization, and kept it with such touching fidelity." This was not the case, as seen in Grandison's eventual departure. The White perception of the slave was not accurate, as slaves proved to be more than what appearances indicated.
The idea of slaves being complex and intricate feeds into another example where things are not always as they seem. Colonel Owens believes that slavery is a life- affirming institution. He sees his slaves as happy and content, confirmed with Grandison's return. Grandison was seen as loyal, trustworthy, and incapable of an action that could be seen as rebellious or, far worse, "uppity." The Colonel believes this at moments throughout the narrative, such as when Grandison says that he was "best marster any nigger ever had in dis worl'." As the Colonel sees Grandison and his family leave, it becomes clear to that what he thought was not actually what was.
Another example could be seen in Dick Owens, himself. Owens is seen as heroic for his perceived accomplishments. Charity marries him because of her belief that he has done something heroic in supposedly freeing the slave. In the end, Dick is no hero. He is more opportunistic than anything else and the perception of him belies the truth behind he and his intent.
Finally, I would suggest that Grandison's character shows that the human condition is not always what it appears to be. The initial impression is that when Grandison returns, his options were so limited that he merely accepted the condition of servitude and enslavement that awaited him. It is perceived that since he did not escape when he went to the North that he would not be able to find any sphere of resistance or any ability to change his state of being. Yet, when Grandison escapes, it is demonstrative of how individual freedom, though challenged, is always there. It lies underneath the surface, percolating to a boil and waiting to be released. Grandison displays this when he leaves, reflecting that what is might not be what it appears to be.