[BowMAN] FUNDAMENTAL PROCESSES IN HISTORICAL SCIENCE 139 
mental; and for convenient identification henceforth in this paper they 
will be designated collectively as the four fundamental principles of 
science and severally as the first, second, third and fourth fundamental 
principles respectively: 

i. THE PRIMARY ATTITUDE TOWARD ALL CONCLUSIONS, WHETHER 
PROBABLE OR IMPROBABLE, MUST BE ONE OF NON-ACCEPTANCE, 
ACCOMPANIED BY A WILLINGNESS TO MAKE THOROUGH EXAMINA- 
TION BY CORRECT PROCESSES AND TO ACCEPT THOSE CONCLU- 
SIONS, AND THOSE ONLY, WHICH ARE SHOWN THEREBY TO BE 
NECESSARY. 
IUustration:—A student is given three liquids, B, C, and D, having 
each of them the colorless appearance of water, and he is asked whether 
any combination of them will produce a mixture with color. On the 
face of things it seems a highly probable conclusion that no mixture of 
colorless liquids could produce one with color. The student, however, 
proceeds to examine. To a quantity of B he adds a quantity of C, and 
to this mixture in turn he adds a quantity of D. After each addition 
the result is still a colorless liquid. He continues the examination, and 
if his previous tests be represented thus: 
1. (B + C = colorless) + D = colorless, 
his subsequent tests may be represented as follows: 
2. (B + D = colorless) + C = colorless, 
3. (C + D = colored) + B = colorless. 
A mixture of C and D apart from B will produce a precipitate, 
1.e., Will result in a colored mixture; but B, if previously added to either 
C or D, will prevent this precipitation, or the subsequent addition of B 
to the mixture of C and D will dissolve the precipitate and restore the 
mixture to a colorless liquid. Thus any chloride and any silver salt, 
e.g., sodium chloride and silver nitrate, give a white (milky) precipitate 
soluble in ammonia; or potassium chromate and lead nitrate give a 
bright yellow precipitate soluble in sodium hydrate (caustic soda). 
This case illustrates not only how necessary in scientific investiga- 
tion is the primary attitude of non-acceptance toward a probable con- 
clusion, but also how necessary is a persistence in that attitude through- 
out an exhaustive examination. The conclusion that a combination of 
colorless liquids could not produce color was not only highly plausible 
in itself, but this view was confirmed throughout the first four of the 
six combinations possible by change either of the ingredients themselves 
or of the order of their mixture represented in the above tests, including 
two mixtures of all the liquids in two different orders; and it was only 
