LUCRUM CESSANS. - By this expression is meant the diminution of patrimony due to the failure to acquire goods which, had a particular event not occurred, would have been acquired. The diminution of patrimony can in fact occur either through the loss of what one already possessed, or through the failure to acquire what one would certainly have come to possess. The first form is called damnum emergens; the second lucrum cessans.
The diminution of patrimony can be considered both on the part of the one who causes it and on the part of the one who suffers it. In this second case it can be of interest above all as a legitimating cause. L. c. can legitimize, for example, the increase in price of what is the share objectively corresponding to justice, the loan at interest, the postponement of restitution, the omission of Mass on a day of obligation. Under the first aspect, that is, considering the diminution of patrimony on the part of the one who causes it, the obligation of restitution is to be emphasized.
It is beyond doubt that whoever has culpably caused a damage is obliged to repair it totally, also as regards l. c. This derives from natural law and is expressly affirmed by the civil codes (cf., for the Italian Civil Code, art. 1223).
However, a difficulty immediately appears. How is l. c. to be evaluated exactly? How is one to establish with precision what a person would have acquired, had a particular fact not occurred? One enters, as can be seen, into the field of future contingencies, that is, into the field of those conditioned developments of history which only God can know with certainty. Men cannot go beyond conjectures, based on what usually happens. For these reasons the evaluation of l. c. cannot be made except on the basis of statistical criteria, drawn from the habitual way in which things unfold. One will have to look to what usually happens, prescinding from exceptionally fortunate cases and from exceptionally unfortunate cases. The Italian Civil Code affirms that « l. c. is evaluated by the judge with equitable appreciation of the circumstances of the case » (art. 2056).
Bibliography2 works
Giovanni Battista Guzzetti