Dementia is a syndrome, not a disease. Dementia is a group of symptoms that affects mental cognitive tasks such as memory and reasoning. Dementia is an umbrella term that Alzheimer's disease can fall under. It can occur due to a variety of conditions, the most common of which is Alzheimer's disease
Courtesy Manners demonstrate ones ability to put the interests of others before oneself; to display self-control and good intent for the purposes of being trusted in social interactions.