Concept of positive, negative conditions

The concepts of positive and negative conditions are discussed on Article 1184 and Article 1185 of the Civil Code of the Philippines, to wit:

ART. 1184. The condition that some event happen at a determinate time shall extinguish the obligation as soon as the time expires or if it has become indubitable that the event will not take place. (1117)

ART. 1185. The condition that some event will not happen at a determinate time shall render the obligation effective from the moment the time indicated has elapsed, or if it has become evident that the event cannot occur.  

If no time has been fixed, the condition shall be deemed fulfilled at such time as may have probably been contemplated, bearing in mind the nature of the obligation. (1118)

The condition that some event happen at a determinate time shall extinguish the obligation is a positive condition. Article 1184 applies if a condition is a positive one. The obligation subject to a positive condition will be extinguished as soon as the time expires or as soon as it has become indubitable that the event will not take place although the time specified has not yet expired.

On the other hand, a negative condition is the condition that some event will not happen at a determinate time shall render the obligation effective from the moment the time indicated has elapsed or if it has become evident that the event cannot occur. Article 1185 applies if a condition is a negative one.