When Mercury is positioned in the 8th house, the native’s intellect receives Plutonic traits, making his mind over-analytical and able to get deep into every subject it concentrates on. Such kinds of people are very focused and have amazing abilities of uncovering secrets. They adore solving mysteries both of the material realm and the occult.
A native with such an aspect may have a great career as a detective, an undercover policeman or a spy. His eyes are always there to focus on the details, while his brain can filter the important information and figure out links between evidence even if it is not profound. They are also able to intuitively understand liars, see gaps in plots of stories and highlight dubious parts. It is very difficult to lie to such an individual.
When Mercury is present in the house of death, the person’s mind is drawn towards the occult. They should be very careful, especially if their Mercury is adversely afflicted, as their words and thoughts have immense power, resulting to effects that can be even be described as “unconscious black magic”. Indeed, whatever negative they wish, say or think can materialize; if their character is grudgy and revengeful they can do a lot of harm to other people. Trying to focus on positive thoughts is an exercise they should always practice, as in the end life tends to return the evil created by someone. The 8th house is an open gate, and sending negativity through it will have a mirror effect back in some other moment.
While 8th house Mercury people adore uncovering secrets of other people, they keep their own well hidden. They strive to keep their thoughts in a fog of mystery, and will easily lie to others in order to create a false image. This technique, even if unconsciously done by such individuals, is a great source of power. They strengthen their thoughts, by not sharing them; the same way that in many religions the real names of gods were not revealed to the masses.
Due to the 8th house also ruling sex, Mercury strongly connects sexuality to the intellect with such a placement. People who have such an aspect will choose partners with whom they can communicate in deep levels, share fantasies and otherwise use speech as a means to transfer sexual energy. Mercury in this house receives a lot of dark, Plutonian attributes, making the individual indulge in games of controlling his partner through words. If the planet is afflicted by Pluto or Mars, there are possibilities of obsessive or manipulative behaviors; in extreme situations this aspect can create stalkers and abnormally obsessed minds. This placement gives a natural disbelief towards others, and someone with this placement would not hesitate to check on his significant other. This might be from looking the messages on the telephone or social media, to even creating real detective-style researches in order to uncover possible infidelities. Indeed, when Mercury is very heavily challenged by malefics, the mind of any native can reach extreme and uncontrolled behaviors, no matter in which sign or house it is located.
On the other hand, such a mind can be a blessing for a writer, a psychologist or someone interested in the other realms and the connections with our reality. They take big pleasure in uncovering the reasons and mechanisms behind things, can easily analyze characters, behaviors and motivations; at the same time, they can foresee the development of strategies – this can also make them great chess players. Their speech is very persuasive, and when they talk they automatically receive a place of authority, which can sometimes be regarded as a manipulative technique and even create enemies in people that do not accept and tolerate such behaviors.
Mercury in the 8th house is a great placement for finances and working in governmental organizations. It is not uncommon that people with such a placement have a career as accountants for the government, in tax departments, banks or big multinational companies; they can also be stock analysts or otherwise work where the big money is. In business, their morals can be rather flexible, and their hidden agendas can even harm people. They usually do not cause harm deliberately; but hey will not blame themselves if something like that happens.
In case of adverse aspects falling on natal Mercury, there can be legal problems with some inheritance. Usually, such problems have to deal with some kind of paper or contract, and it depends on the nature of the planet afflicting Mercury on whether the story will have a happy end. There are possibilities of them losing a sibling or important neighbor while young; this issue should be observed more though through the 3d house and its ruler.
Finally, when the planet of speech is placed in the darkest house, it definitely creates a person using black humor. Indeed, such individuals like sarcasm, enjoy readings where even morbid areas like death are seen with a pinch of salt and like to laugh towards everything that is a taboo. These are the type of people when see a human scull will take it in their hands and start making fun jumping on a grave and shouting “To be or not to be, that is the question”. Fun people to hang around, unless of course you become the victim of their weird sense of humor, which is many times difficult to understand whether hides some inner aggression and malice towards you. As we already said, these people tend to hide their real thoughts, and a genuine positive behavior could be appearing as malignant. Or the opposite.