The principle of the conservation of energy is therefore subject to limitations which are supplied by the principle of the dissipation of energy. It simply asserts that, so far as our observation extends, the whole amount of potential and kinetic energy in the universe is invariable, but it can not determine whether the amount of vital force, or of psychic force, is invariable; and it is certainly incompetent to fix a limitation to the exercise of Creative Power. "It is nothing more than an intelligent and well-supported denial of the chimera of perpetual motion, and that a machine can no more create work than it can create matter."[465] In the words of Grove, we can not conceive of the production of any new force in the universe "_without the interposition of Creative Power_."[466] Dr. Tyndall, in his solicitude to exclude all Divine interposition in the economy of nature, has stated the law of the conservation of energy in a form quite different from that of his scientific brethren. He says, "The principle of conservation is, _no creation_ but infinite conversion;"[467] and he seems desirous to convey the impression that any interposition of God to answer prayer would be a creation of physical force, and as much a miracle as the rolling of the waters of the St. Lawrence up the Falls of Niagara. Dr. Tyndall does not here display his usual fairness and candor. Surely he would not assert that the qualitative and quantitative combination of the different natural agents--such as light, heat, electricity, elasticity of vapors, and aerial currents--which determine the fall of a shower of rain, would be a _creation_ of energy; or that the disposition of the meteorological, physical, chemical, vital, and psychical conditions which result in the cure of the sick, would be as much a miracle as "the stoppage of an eclipse;" for these natural agents are more or less under the control of man. But suppose it were granted that all interposition of God in the economy of nature must be regarded as _miraculous_, would he deny the possibility of miracles even if they should involve a creation of energy? Because we can not by any of our mechanical arrangements create energy, does it therefore follow that God can not create energy? Dr. Tyndall will not say this. "If you ask who is to limit the outgoings of Almighty power, my answer is--not I."[468]