EMPLOYMENT PSYCHOLOGY 
worked at the occupation, he has already available some 
skill, trade knowledge, and judgment which will shorten his 
period of training for this particular job. These abilities 
should be measured—tested by means of an adequate sam- 
pling of typical standardized occupational tasks, information 
items, and judgment problems. If, on the other hand, the 
applicant has had no experience in this vocation, his ability 
to handle a sample of the work, and particularly the rate at 
which he acquires this new ability, may be an indication of 
his future success at the job. The investigator will, of 
course, interpret all measurements in the light of his infor- 
mation as to the worker’s previous education, experience, 
and opportunities to learn; he may even find it advantageous 
to get the facts about the interests and occupational accom- 
plishments of parents and grandparents. But he need not 
trouble himself as to whether the observed relation between 
parental success and achievement of offspring is due to the 
forces of heredity or of environment. The distinction be- 
tween native and acquired abilities may safely be ignored. 
GENERAL AND SPECIFIC ABILITIES 
A similar haze envelops the distinction between specific 
abilities and general abilities, but the controversies over this 
subject cannot be so promptly dismissed. An appreciation 
of the problem, at least, is helpful to an understanding of 
much current writing on vocational selection. 
Every one believes in specific abilities. A person’s 
achievements in occupation or profession are conditioned 
by the excellence of a large number of readily distinguish- 
able characteristics, each independent, to some degree at 
least, from all the others. The question which has long 
concerned psychologists is, whether a man’s ability as a 
whole is essentially a summation of these specific abilities. 
Are there not certain common factors involved in all of a 
man’s behavior? Are there not at least a few general abilities? 
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