If there is a life very much different from and very much higher than our present one, it is not strange we are ignorant of it. It is impossible to make a person understand anything which is entirely unlike all that has ever been seen or heard, for every idea in the world that man has came to him by nature. Man[79] cannot conceive of anything the hint of which has not been received from his surroundings. He can imagine an animal with the hoof of a bison, with the pouch of a kangaroo, with the wings of an eagle, with the beak of a bird, and with the tail of a lion; and yet every point of this monster he borrowed from nature. Everything he can think of, everything he can dream of, is borrowed from his surroundings--everything. "So, if an angel should come and tell of another life, it would mean nothing to us, unless we could translate it into terms of our own experience. We could not understand a 'light that never was on land or sea.' Our ignorance is not even then a probability against our belief."[80] As has already been stated, the visible universe must have its doom, must end as it began, by consisting of a single mass of matter; but is there not a more primitive state of matter than the matter such as we know it? Yes; and the so-called ether is that matter. It is unlike any of the forms of matter which we can weigh and measure. It is in some respects like unto a fluid, and in some respects like unto a solid. It is both hard and elastic to an almost inconceivable degree. "It fills all material bodies like a sea in which the atoms of the material bodies are as islands, and it occupies the whole of what we call empty space. It is so sensitive that a disturbance in any part of it causes a 'tremor which is felt on the surface of countless worlds.' It exerts frictions; and although the friction is infinitely small, yet as it has an almost infinite time to work in, it will diminish the momentum of the planets, and diminish their ability to maintain their distance from the sun, the consequence of which will be the planets will fall into the sun, and the solar system will end where it begun."[81] According to Sir William Thompson, the ultimate atoms of matter are vortex rings, which Professor Clifford describes as being more closely packed together (finer grained) in ether than in matter. And he says, "whatever may turn out to be the ultimate nature of the ether and of molecules, we know that to some extent at least they obey the same dynamic laws, and that they act on one another in accordance with these laws. Until therefore it is absolutely disproved, it must remain the simplest and most probable assumption that they are finally made of the same stuff, that the material molecule is in some kind of knot or coagulation of ether."[82]