Vastu-purusa means in the present context a site-plan or a location plan. According to the Matsya Parana, the Vastu Purusa Mandala has particular deities of Vastu Purusa in respective places. The North-East (aisdnya) is said to be occupied by Mercury (budha) and Lord Vishnu. Accordingly, the place of conducting mental work and the worship chamber in a ruse is to be situated in that direction.
The South-East (agrneyi) is said to be occupied by the Moon and Parvati. The Moon is said to be the controller of mind and Parvati is the symbol of mother, of mind. Frailty is the nature of mind. If Parvati becomes the redressessor of the house-hold, her place like that a house is in that direction. Cooking room is to be in the South-East. The North-East (Aisdnya) is said to be occupied by Ketu and Chitragupta. So it is recommended that treasury accounts and store should be on that side.
It is a rule that pillars are not to be raised on the sensitive points of Vastu Purusa. The sensitive points according to the science of physics axe inlets and outlets. It is presumed that the Vastu Purusa would suffocate if inlets and outlets are blocked with pillars. The sensitive points exist also on the folds of the arms and legs. Pillars, if erected on those points, would not find enough base and support. Therefore, those points are to be avoided for pillars.
The head of the Vastu Purusa is at the Aisanya. The head should be secure. It appears, therefore, that the North-East is to be kept free from heavy structures like pillars, etc.
Legends of Vastu Purusha
There are many stories regarding Vastu Purusa. As per the Hindu Mythology, in a war between Devas and Asuras, a demon appeared and started torturing the Devas. Ultimately the Devas pushed him down and sat over him. The demon appealed to Lord Brahma for help. Lord Brahma named him Vastu Purusa and blessed him with the words: "All works on the earth will have to be commenced and concluded only after propitiating you." In essence, without Vastu Purusa nothing will happen on the earth. The Vedas also give similar ideas to Visvakarman or Vastu Purusa.
People think that construction of a house or abode is nothing but construction with bricks and mortar as per the plan. There are various aspects to be considered and consulted before and during construction. Even the position of doors (especially front door) and windows and the direction in which an entrance to the house is fixed, have a lot of significance in the well-being of owner and residents. The position of Vastu Purusa and the direction of natural elements are shown in the diagram below. It shows all the Five Elements created by the Creator, Lord Brahma, in this Universe.