Mind is invisible force in our body driving and directing our thinking, attitude, emotions, actions and reactions. Mind is not a gross thing, it is invisible and intangible. Its magnitude cannot be measured. It does not require a space in which to exist. Mind is the most subtle of the matter and hence, prompter of the body. Its seat is in the brain and the mind is not brain. Many misunderstand mind to brain. For the better understanding of the modern society, the brain can be compared with the CPU of a computer, mind the operating system. The mind is intimately connected with the body. The mind acts upon the body and the body reacts upon the mind. Mind has influence over the body. A pure healthy mind means a healthy body. Grief in the mind weakens the body. Body influences the mind also in its turn. If the body is healthy, the mind also becomes healthy. If the body is sick, the mind also becomes sick. Pain in any part of the body causes depression in the mind. Mind is also the thinking faculty, that which schemes, plans, reasons, wanders, fluctuates, soars high, falls low, rejoices, feels sad and depressed, concentrates in Peace, degenerates in ignorant darkness. All these changing faculties are made up of Mind. Mind is a link to the outer plane of phenomenal existence by means of its servants: the senses, and the inner realms through intellect. It helps to know, that the mind is never separate from the little Self, and the higher Self, just as a drop of water in the ocean is never separate from the waves or the waves from the ocean. Whether the wave rises or falls, it is inseparably connected with the ocean. Similar is the case with the mind, with the supreme Spirit. Power of the mind that actually makes difference, in the evolution of human personality. For better understanding, let us take an example from the field of physics, where we are familiar with the similar phenomenon: Ordinary light is a radiation of very little penetrating capacity. But X-ray by increase in the wave frequency of the radiation, science has developed radiation of greater and greater penetrating capacities. The similar phenomenon of the physical world, we also find in the mental world. The average mind which is untrained, un-disciplined and dull in its operation; it stops at the very surface of experience. It cannot penetrate the surface of the problem in order to find a solution to the problem. It cannot even raise the question: like, is there any solution to this problem? Such is the raw and untrained human mind. Yet same mind can be trained and disciplined and made penetrating in its power; thus we get the scientific and philosophical mind, which has disciplined itself in the systematic inquiry and investigation into the universe of sensory experience. As a result of this discipline, the mind gets the power to excise control over the sensory and motor organs of the human system which, formally was under the direct dictation of the sense-impressions and instinctual impulses. If a scientist stop there and refuses to proceed further in the research for truth, it is because he is forsaken his scientific spirit and become sterile or dogmatic. Why should he stop there? If the mind can be trained to penetrate some, by still with greater discipline it can be trained to penetrate the whole. This is the most fascinating and intriguing subject for the human mind; through baffled again and again, the mind will return to it again and again. One may try to drag the mind away from such fundamental questions; one may adopt philosophies of positivism and humanism and try to direct the mind either to living a better life. Or to do the good to himself and the world. Senses conceal more than they reveal.