The game of life is an excellent framework for metaphysical modeling. It can be used to study ontological categories like space, time, causality, persistence, substance, emergence, and supervenience. It is often said that there are many levels of existence in the game of life. Objects like the glider are said to exist on higher levels. Our goal here is to work out a precise formalization of the thesis that there are various levels of existence in the game of life. (...) To formalize this thesis, we develop a set-theoretic construction of the glider. The method of this construction generalizes to other patterns in the game of life. And it can be extended to more realistic physical systems. The result is a highly general method for the set-theoretical construction of substances. (shrink)

Air is one of the five classical elements, which make all the creation. We can perceive air in the things it moves, be it leaves or hair. It is an invisible mixture of nitrogen, oxygen, and minute amounts of other gases surrounding the Earth. It is all around us. Yet, we cannot see it. Pure air has no odour. It has many uses. It provides a breath of life to all living beings. As, atmosphere, it prevents the excessive heat of (...) the Sun from reaching us. Oxygen, one of its constituents, supports combustion. Thereby it helps us to cook food, generate heat and electricity, run industries and drive vehicles. Its other two components, nitrogen and carbon dioxide, are essential for the growth of plants. Another beneficial constituent of air is Ozone, which in the form of the Ozone layer around our planet protects us from the adverse effects of the Sun's UV rays. Compressed air is used to fill tyres. Many machines and drills work on compressed air. Wind enables the movement of sailboats and gliders. It runs windmills to generate electricity and helps in the dispersal of seeds. Guru Arjan appreciating the priceless importance of air to all of us articulates [1-2]; He (Creator) gave you the invaluable air. (Mehl 5, SGGS, p 913). (shrink)