In most cases, there is no difference between animal and man. Both are easily manipulated and molded to act a specific way or believe a certain ideal. In George Orwell's story, Animal Farm, characters such as Boxer, Bluebell, Jessie, Pincher, and the sheep, demonstrate the mental vulnerability that benefits Napoleon as a dictator.
The dogs Bluebell, Jessie, and Pincher's naive mentality gives Napoleon an opening to initiate severe oppression on the farm animals. For example, because they are young and able to absorb new ideas and beliefs, they are easily brainwashed. They are trained to be guard dogs for Napoleon like the nine other dogs who drive Snowball out of the farm, giving Napoleon an advantage to gain to absolute power. One of a dictator's goals is to have their people catechized as young as possible, that way their power is more likely to succeed.
Boxer, the hard-working horse, represents a blind follower. He gives Napoleon absolute faith and trust -- but unfortunately, blinded by the propaganda of extreme nationalism, he does not fully grasp the situation. For instance, "I will work harder" and "Napoleon is always right" (75) is his answer for everything. Boxer is described as a powerful horse who has the capability to overthrow Napoleon's reign -- but his mentality is not quite there to see what is really going on. He chooses not see the reality of the situation, but rather what the situation he yearns for which is freedom. In order to get that freedom, he must devote himself blindly to optimism and the hard work he believes will benefit him and the animals of Animal Farm in the future. The oppression becomes heavier and malignant to the malnourished animals -- yet the animals put their pain aside, believing good will eventually come.
The reason why most people are called sheep, is because sheep are known to be followers by design. The group mentality is designed to follow a single leader for their own survival -- never questioning who the leader is. For example, "Four legs good, two legs bad!" (63) and the lack of understanding the amendments -- let alone the inability to read, show how dependent and trusting they are because they follow whatever Napoleon says. They don't know how to think for themselves, giving Napoleon the obligation to help "guide" them in the right path -- when in all actuality, it benefits his power. Of course the sheep do not object the harshness of Napoleon's rule, because they believe that Napoleon knows best due to his intelligence and security. Calling them "Comrade", ensures that Napoleon will forever be their equal -- giving every animal enough credence to drive them away from independent thoughts and taking advantage of their susceptibility and loyalty.
In most cases, there is little to no difference between animal and man. They are easy to exploit and shape to become what the architect desires them to be to fulfill their goals. In Orwell's story, the lack of knowledge and understanding of Bluebell, Jessie, Pincher, Boxer, and the sheep elucidate the reasons of Napoleon's dictatorial maltreatment towards the animals of Animal Farm. If characters like Boxer focused and followed their own notions instead of Napoleon's, he would have been able to overthrow the dictator and his guard dogs -- along with converting everyone's belief.