If this be granted as a fact of our everyday experience, we naturally ask: “Why are things so changeable? Why is life so fleeting? What is it that makes things so mutable and transitory?” To this, the Buddhist’s answer is: Because the universe is a resultant product of many efficient forces that are acting according to different karmas;--the destiny of those forces being that no one force or no one set of forces can constantly be predominant over all the others, but that when one has exhausted its potential karma, it is replaced by another that has been steadily coming forward in the meantime. Hence the universal cadence of birth and death, of the spring and the fall, of the tide and the ebb, of integration and disintegration. Where there is attraction, there is repulsion; where there is the centripetal force, there is the centrifugal force. Because it is the law of karma that at the very moment of birth the arms of death are around the neck of life. The universe is nothing but a grand rhythmic manifestation of certain forces working in conformity to their predetermined laws; or, to use Buddhist terminology, this _lokadhâtu_ (material world) consists in a concatenation of _hetus_ (causes) and _pratyayas_ (conditions) regulated by their karma. {143} If this were not so, there would be either a certain fixed state of things in which perfect equilibrium would be maintained, or an inexpressible confusion of things of which no knowledge or experience would be possible. In the former case, we should have universal stagnation and eternal death; in the latter case, there would be no universe, no life, nothing but absolute chaos. Therefore, so long as we have the world before us, in which all the possible varieties of particularisation are manifested it cannot be otherwise than in a state of constant vicissitudes and therefore of universal transitoriness. Now, the Buddhist argument for the theory of non-ego is this: If individual existences are due to relations obtaining between diverse forces, which act sometimes in unison with and sometimes in opposition to one another as predetermined by their karma, they cannot be said to have any transcendental agency behind them, which is a permanent unity and absolute dictator. In other words, there is no âtman or ego-soul behind our mental activities, and no thing-in-itself (_svabhâva_), so to speak, behind each particular form of existence. This is called the Buddhist theory of non-âtman or non-ego. _Âtman._ Buddhists use the term “âtman” in two senses: first, in the sense of personal ego,[65] and secondly, in {144} that of thing-in-itself, perhaps, with a slight modification of its commonly accepted meaning. Let us use the term “âtman” here in its first sense as equivalent to _bhûtâtman_, for we are going first to treat of the doctrine of non-ego, and later of that of no-thing-in-itself.