The concept of the Infinity of Space is one of the fundamental ideas of Buddhism and is based on direct spiritual experience, achieved by the systematic exploration of the mind in the process of meditation. It was known as one of the four higher state of yoga experience before the advent of Buddhism itself. The qualities of space or Akasa itself, is associate with vibration radiation and movement, movement in the sense that there is a 'non-existence’ of obstruction. We can experience and explore visible space outwardly turning it into the observation of external optical space and filling it with objects of our sense perception. On the other hand, we can also turned it in the opposite direction, regarding it as a projection or an imperfect reflection of the inner experience and dived into the center of our own being, into the depth of our consciousness, into which the whole infinite world is contained.
Directedness and movement are the characteristics of Buddhist space experience and can be found in the religious ideas and meditative practice. A good example is seen in the description of the four divine states of mind or the four Brahma Viharas. This meditative practice need us to radiate love, compassion, sympathetic joy and equanimity, first in one direction, then in a second direction, likewise in a third and fourth direction and also equally to the regions above and then below us. We should embrace every sentient being everywhere in the whole world with our love, compassion, sympathetic joy and equanimity, with a deep unlimited mind that is purified from ill-will and aversion. It is necessary to direct our fully conscious mind and radiate unceasingly these divine states of mind towards each of the six directions until the consciousness becomes identified with the universe, filling out the entire infinity of space and leaving no room for the ego to arise. This is a space which is built up in our consciousness by movement and direction. The external space here is nothing more than just a mere reflection, limited by the finite qualities of our eyes, a physical faculty of vision, a space filled with light resisting objects as interpreted by our inner space consciousness
In the higher stages of absorption meditation, the relationship between space and consciousness can also be seen, where if the consciousness of the infinity of space becomes the object of meditation, the experience of infinity of consciousness will arise, after all things and form-ideas are eliminated in the meditation of infinity of space . Space here has two properties, that of Infinity and Nothingness, i.e., non-materiality, these two properties are the expressions of space experience. During an intuitive experience, consciousness will identify itself with the object of meditation. If it is an infinite one, the consciousness will also become infinite and unlimited, and consciousness itself will then become aware of its own boundlessness. In a similar way, the consciousness of emptiness of the absence of all material or imagined ‘things’, of Nothingness, becomes the object of the last stage of absorption. This last stage consists of just an awareness of the emptiness of consciousness called the state of ‘neither perception nor non-perception’. The common denominator of all these states of meditation is based on the concept and basic experience of space, a progressive unification from our surface consciousness to the oneness of our depth consciousness.
It is this profound space experience of meditation that can eventually satisfy our urge for the infinity, which denoted the complete absence of ‘thing-ness’ and limitation and which also symbolize the inexpressible. It is also from this experience too, that the philosophical idea of Sunyata drew its inspiration and on this basis does the concept of Emptiness begin to be become more understandable.