When people do not like you, they will viciously assault your self-perception of intelligence, hard-workingness, reasonability, etc. Anyone can see this happening on an almost daily basis. Whenever one person disagrees with another, that person's first course of action is usually to call the other person stupid. I argue that the first person does this for two reasons.
First, the accuser intends for surrounding people to believe the claim, since if the opponent possesses no intelligence, no one need listen to his or her arguments. Would someone, for instance, listen to a retarded person? No, and the accuser believes that less people will listen to his or her opponent if they believe the opponent to be stupid. This really hits someone below the belt, but it happens in almost every debate imaginable.
Second, and many people do not think about this, the accuser intends to damage the opponent's self-esteem. People tend to derive much of what they think about themselves from the opinions of others. Humans are profoundly social beings. So, if an accuser can convince an opponent him or herself that the opponent has no intelligence, this serves to depress the opponent and to prevent his or her further attempts to demonstrate the opposing position. The opponent simply does not desire to argue anymore because the opponent feels depressed.
Both of these strategies hit below the belt. In the first case, the accuser poses a lie against his oer her opponent intending to discredit the opposing position without tending to the arguments. In the second case, the accuser intends to use the accuser's own influence and the influence of others whom the accuser may convince in order to convince the opponent him or herself that the opponent either has an unsound argument or has an argument less important than the pain of rejection.
If you know something that others do not know and that they do not want to hear, expect not only to be publicly accused of being unintelligent, expect the opposition to literally try to convince you youself that this is true. Do not for one second believe them, as this will modify your motivation in such a way that would make it significantly more difficult to proceed. Your biology will not care how right you are, since your biology has been tasked with keeping you alive and maximizing your biological fitness.