This ability is known as "narcissistic perception," and it may be due to certain shared traits and behaviors among narcissists. Here are a few factors that might contribute to this phenomenon:
Similar Attractiveness: Narcissists are often attracted to others who share their level of attractiveness, charm, or social status. They may recognize these qualities in other narcissistic individuals.
Shared Behaviors: Narcissists may exhibit similar behaviors and tactics, such as seeking attention, admiration, and dominance. When interacting with others who behave similarly, they might perceive a sense of familiarity.
Mirror Imaging: Narcissists tend to see the world in terms of their own needs and desires. When they encounter someone with a similar worldview, they may perceive that person as being like themselves.
Empathy Deficits: Narcissists often lack empathy and may be less attuned to the emotions of others. However, they may be more attuned to the overt self-centeredness of fellow narcissists.
It's essential to remember that not all individuals who appear narcissistic are actual narcissists. Some people may display narcissistic traits due to other factors, such as situational stress or personality disorders other than Narcissistic Personality Disorder (NPD).
Moreover, the ability to identify narcissists can vary depending on the individual and their level of narcissism. Not all narcissists are equally skilled at recognizing others with narcissistic tendencies, and some might be better at it than others.
In any case, diagnosing someone with narcissism or any other personality disorder requires a trained mental health professional to conduct a thorough assessment. Self-diagnosing or diagnosing others based solely on observations or pop psychology is not reliable or accurate.