TRANSACTIONS OF TEE SECTIONS. 



Section A.— MATHEMATICAL AND PHYSICAL SCIENCE. 

 President of the Section.— G. Johnstone Stoney, M.A., F.R.S., M.R.I.A. 



THURSDAY, AUGUST 21, 1879. 



The President delivered tlie following Address : — 



In order that we may understand the present position of Natural Science upon 

 the Earth, we must remember that the universe is in itself one great whole, which 

 includes minds no less than bodies, for thought is as much a phenomenon of what 

 really exists as motion. But though the universe be but one, man with his limited 

 powers is unable to treat it as such, but has to push his investigation of Nature 

 when and where he can. Thus have arisen many sciences which were at first quite 

 isolated. Their separate condition is a mark of the feebleness of our powers of 

 investigation. Their gradual convergence, and especially where any complete con- 

 tact can be established between them, is the mark that our advancing knowledge is 

 penetrating deeper. 



That there are many sciences of Nature, instead of one science of Nature, has its 

 relation, then, to human imperfection. But the coalescence of sciences has com- 

 menced, and is steadily taking place ; magnetism is no longer isolated from electri- 

 city, nor light from heat, nor the power of thinking from the condition of the brain. 

 In all such cases we have got nearer to understanding what is really going on in 

 Nature. There are already many such achievements of science ; but, nevertheless, 

 it remains true that human powers of investigation are so narrow, and the use we 

 have made of them up to the present is so short of what we may reasonably look 

 for in the future, that the sciences of Nature are still many, and most of them stand 

 lamentably aloof from one another. 



We find, then, in the present passing condition of our knowledge, one group 

 of sciences which investigate the phenomena of consciousness; another distinct 

 group of the biological sciences ; and a third, the group of the physical sciences. 

 These are all but parts of the one great investigation of Nature, but for the present 

 they exist almost disconnected, as separate provinces of human inquiry. 



When we endeavour to investigate mental phenomena, we are encountered by 

 the complexity and remoteness of the effects which present themselves for exami- 

 nation, and by a deep and impenetrated obscurity hanging over the interval 

 between them and their causes. In order to make any progress even in the sub- 

 ordinate task of tracing out the relations of these effects to one another, the inquirer 

 finds it necessary to venture upon hypothesis, and in all metaphysical speculation 

 we sadly miss that healthy discipline with which Nature in other branches of 

 science relentlessly refutes our hypotheses if they are wrong. Here, then, is a 

 region in which the plausible may be mistaken for the true ; and it is unfor- 

 tunately certain that it has sometimes been so mistaken by the ablest human 

 minds. 



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