EMERSON HALL 
21 
times have changed and that their speech is the wisdom of yesterday. 
In the history of human knowledge the periods alternate. Great 
waves follow each other, and while one tendency of scientific thought 
is ebbing, another is rising; and there is no greater alternation than 
that between positivism and idealism. The positivistic period of 
natural science has ebbed for ten or fifteen years; an idealistic one 
is rising. Emerson once said here in Harvard that the Church has 
periods when it has wooden chalices and golden priests, and others 
when it has golden chalices and wooden priests. That is true for the 
churches of human knowledge too, and for knowledge of all denomi¬ 
nations. Forty, fifty years ago, in the great period when Helmholtz 
discovered the conservation of energy and Darwin the origin of species, 
one naturalistic triumph followed the other, golden high priests of 
natural science were working with wooden chalices in narrow, 
awkward laboratories; to-day natural science has golden chalices 
provided in luxurious institutions, but there are too many wooden 
priests. The fullest energies of our time are pressing on to an ideal¬ 
istic revival, are bringing about a new idealistic view of the world, and 
turning in sympathy to that last foregoing period of idealism of which 
Ralph Waldo Emerson was perhaps the last original exponent. But 
also with his period idealism was not new. When he came to speak 
on the Transcendentalist, he began, “The first thing we have to say 
respecting the new views here in New England is that they are not 
new.” Yes, indeed; since the beginnings of Greek philosophy, 
more than two thousand years ago, the two great tendencies have 
constantly followed each other. Each one must have its time of de¬ 
velopment, must reach its climax, must go over into undue exagger¬ 
ation, and thus destroy itself to make room for the other, which then 
begins in its turn to grow, to win, to overdo, and to be defeated. 
_ Glorious had been the triumph of Positivism in the middle of the 
eighteenth century when the French encyclopaedists were at work, 
those men who wrote the decrees for the French Revolution. But 
before the last consequences of the Positivism of the eighteenth cen¬ 
tury were drawn, the idealistic counter-movement had started. Im¬ 
manuel Kant gave the signal, he fired the shot heard round the world; 
and Fichte followed, whose ethical Idealism changed the map of 
Europe, and his spirit went over the Channel to Carlyle, and finally 
over the ocean to these shores of New England and spoke with the 
lips of Emerson. It is unimportant whether Emerson studied the 
great transcendental systems in the original; he knew Kant and 
Schelling probably at first through Coleridge, and Fichte through