Then _Antecedents_ _Consequent_ X no. of cal. of heat in room = 68° F. temp. of room X no. of cal. of heat + burning candle = 68° + 2° = 70° X (no. of cal. of heat + burning candle) = (68° + 2°) − 2° = 68° − burning candle As large “A” is increased and decreased by little “a” so large “P” appears to be increased and decreased by little “p.” This strongly suggests a causal connection between little “a” and little “p.” (3) Other concrete illustrations. _Problem_: To ascertain nature of sound. _Antecedent_ _Consequent_ Bell rung when within a glass jar filled Loud sound. with air, Some of the air pumped out of the jar, Sound not so loud. More air pumped into jar again, Sound louder again. The conclusion must be that air has something to do with the production of sound. _Problem_: To find best feed for egg production. 100 lbs. beef scraps, } 100 lbs. wheat, } 30 doz. eggs. 100 lbs. oats, } 100 lbs. corn, } 50 lbs. beef scraps, } 100 lbs. wheat, } 27 doz. eggs. 100 lbs. oats, } 100 lbs. corn, } 90 lbs. beef scraps, } 100 lbs. wheat, } 28 doz. eggs. 100 lbs. oats, } 100 lbs. corn, } Since the variation in the amount of beef scraps is accompanied by a like variation in the number of eggs produced, it may be assumed that beef scraps are essential to large egg production. (4) Distinguishing features. The phenomenon always occurs but in varying degrees; One antecedent varies in degree; The other antecedents are invariable. (5) Advantages and disadvantages. Concomitant Variations is applicable in cases when it is impossible to use Difference. Recourse is made to the latter when the phenomenon can be made to appear or disappear at will, but there are times when it is impossible to cause the phenomenon to disappear altogether. For example, in the case of the varying degrees of heat in the room it would be scientifically impossible to take _all_ of the heat out of the room; or in experimenting with gravitation, to do away with its influence entirely, is beyond the power of man. It is thus evident that Concomitant Variations may be used in cases where the conditions forbid doing away entirely with the phenomenon.