The Relation of Science and Religion.pdf - Online Christian Library

LIFE AND ITS DE YELOPMENT. 131ment originates.* This depends for its developmenton external conditions such as heat andmoisture.-/- Advance in the scale is connectedwith greater complexity in the organism. Aswe ascend, separate organs appear, fulfillingdistinct functions, and controlled by means ofa nerve system whose ramifications are accordingto the intricacy of the organism. Theappearance of such a nerve system impliessensibility and motor activity, provision foran experience more or less varied, and movementin some measure according with it, oradapted to it. From a nerve system consistingof a cent're and a few fibres, we graduallyascend, until in the higher vertebrate orders,we find a vast system of nerves harmonizedand governed from a grand centre or terminusconstituting the brain.$ With the steadilyadvancing complexity of nerve system, thereis great diversity in the orders of animals, inthe variety of actions of which they are capable,in adaptation to different conditions oflife, and in the nodes in which they obtainsubsistence. The scientific problem is-Howfar can we account for all this coinplex systemof thipgs by the action of natural ca.uses?As we are here specially concerned with* See Appendix VII. t See Appendix V. f See Appendix IV.