98 Edward Livingston Youmans. 



state of things has been deeply disturbed. The introduc- 

 tion of republicanism, with political freedom of speech and 

 action ; the advent of Protestantism, with religious liberty 

 of thought; and the splendid march of science, which has 

 enlarged the circle of knowledge, multiplied the elements 

 of power, and scattered social and industrial revolution 

 right and left for the last hundred years these new dis- 

 pensations have invaded the old repose and fired the minds 

 of multitudes with a new consciousness of power. Yet we 

 cannot forget that our education still retains much of its 

 ancient spirit, is yet largely scholastic and arbitrarily au- 

 thoritative. We believe that this evil may be to a consid- 

 erable degree corrected by a frank admission of the incom- 

 pleteness of much of our knowledge ; by showing that it is 

 necessarily imperfect, and that the only just and honest 

 course often involves reservation of opinion and suspension 

 of judgment. This may be consonant neither with the 

 teacher's pride nor the pupil's ambition, nevertheless it is 

 imperatively demanded. We need to acquire more humility 

 of mind and a sincerer reverence for truth ; to understand 

 that much which passes for knowledge is unsettled, and 

 that we should be constant learners through life. The 

 active influences of society, as well as the schoolroom, 

 teach far other lessons. We are committed in early child- 

 hood to blind partisanships political and religious and 



drive on through life in the unquestioning and unscrupu- 

 lous advocacy of doctrines which are quite as likely to 

 be false as true, and are perhaps utterly incapable of 

 honest definitive adjustment. Science inculcates a differ- 

 ent spirit, which is most forcibly illustrated in those 

 branches where absolute certainty of conclusion is difficult 

 of attainment. 



Coming to the details of his volume, after pointing- 

 out that while the principal statements in the chapters 

 on heat, light, and air were comparatively well estab- 



