342 ON THE ADVISABLENESS OF 



which have been rendered possible only by the progress of 

 natural knowledge in the direction of mathematics, and the 

 accumulation of wealth in virtue of other natural knowledge. 



But the plague ? My Lord Brouncker's observation 

 would not, I fear, lead him to think that Englishmen of 

 the nineteenth century are purer in life, or more fervent in 

 religious faith, than the generation which could produce a 

 Boyle, an Evelyn, and a Milton. He might find the mud 

 of society at the bottom, instead of at the top, but I fear 

 that the sum total would be as deserving of swift judgment 

 as at the time of the Restoration. And it would be our 

 duty to explain once more, and this time not without 

 shame, that we have no reason to believe that it is the 

 improvement of our faith, nor that of our morals, which 

 keeps the plague from our city ; but, again, that it is the 

 improvement of our natural knowledge. 



We have learned that pestilences will only take up their 

 abode among those who have prepared unswept and un- 

 garnished residences for them. Their cities must have 

 narrow, unwatered streets, foul with accumulated garbage. 

 Their houses must be ill-drained, ill-lighted, ill-ventilated. 

 Their subjects must be ill- washed, ill-fed, ill-clothed. The 

 London of 1665 was such a city. The cities of the East, 

 where plague has an enduring dwelling, are such cities. 

 We, in later times, have learned somewhat of Nature, and 

 partly obey her. Because of this partial improvement of 

 our natural knowledge and of that fractional obedience, 

 we have no plague; because that knowledge is still very 

 imperfect and that obedience yet incomplete, typhus is 

 our companion and cholera our visitor. But it is not pre- 

 sumptuous to express the belief that, when our knowledge 

 is more complete and our obedience the expression of our 

 knowledge, London will count her centuries of freedom from 

 typhus and cholera, as she now gratefully reckons her two 

 hundred years of ignorance of that plague which swooped 

 upon her thrice in the first half of the seventeenth century. 

 Surely, there is nothing in these explanations which is 

 not fully borne out by the facts ? Surely, the principles 

 involved in them are now admitted among the fixed beliefs 

 of all thinking men ? Surely, it is true that our country- 

 men are less subject to fire, famine, pestilence, and all the 

 evils which result from a want of command over and due 

 anticipation of the course of Nature, than were the country- 

 men of Milton ; and health, wealth, and well-being are more 



