Analysis on combinations of solidary and joint debtors or creditors

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In an obligation to pay Php100 wherein there are two debtors and two creditors, what are the rules?

Since the law does not presume the solidary nature of debt or credit, it is presumed that there are two joint debtors and two joint creditors: A, B, (debtors) C and D (creditors). When we say the law presumes the joint nature of debt and credit, we mean that the law presumes that:
  1. C gave Php25 to A and another Php25 to B; while
  2. D gave Php25 to A and another Php25 to B.
Hence, in the example above, when the debt becomes due and demandable, A cannot be presumed to have the obligation to pay for B, and vice versa. Also, C cannot be presumed to have the agency to collect from both A and B the whole debt (i.e. Php100). As a result, C can only collect Php25 from A and collect Php25 from B, thereby completing the Php50 to which C is entitled to as a joint debtor. The same is true for D.

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