The number 7 is the seeker, the thinker, the searcher of Truth (notice the capital "T"). The 7 doesn't take anything at face value -- it is always trying to understand the underlying, hidden truths. The 7 knows that nothing is exactly as it seems and that reality is often hidden behind illusions.
A person who has a chart dominated by the 7 is usually easily picked out of a group. He will be somewhat introverted, perhaps shy (not to be confused with low self-esteem), never truly comfortable in social settings. The 7 is the intellectual, but his intellect is not always obvious, especially at an early age (as a child, Einstein was dyslexic and not particularly bright or a good student). His intelligence is that of a dreamer, an intellectual explorer of the obscure, the person who tends to have a somewhat off-beat perspective on the world around him. Many are interested in the metaphysical, not because they are believers, but because it allows access to the ambiguous, abstract world of questions for which there are no clear answers.
The 7 is spiritual, but not religious. In fact, the age-old questions of what life is all about, why am we here, who am we, and so forth, never reach the status of clichés, but are essential to the 7's life-experience, and unless he finds the answers he will not stop looking for them until he dies.
The 7 can be aloof, hates gossip and is immune to small-minded backstabbing. Money means nothing to him and he will never make a choice or a decision based on an expected financial outcome.
There is a dry, usually misunderstood sense of humor to the 7, yet he is unable to remember a single joke. He is not jovial and never superficial. He has excellent taste and a natural love and understanding of art. He dislikes and completely ignores fashion, and is attracted to eccentric, unpopular people. The popular "beautiful" but shallow people bore him to no end. He is not usually interested in politics but has a strong sense of justice.
The 7 is physically lanky and tall, but not athletic and doesn't care about sports. 7s are not warriors, but you may find some people with the 7 dominating their charts in the military, most likely as analysts or strategic planners. More often, however, you will find them in the world of academics and science. Police detectives, laboratory researchers and other careers where logical, methodical analysis of facts are the main requirements of the job.