by which ideas are represented on material substances. Documents are either public or private writings.17. Distinction between Public Documents and Private Writings.(a) Authenticity: A public document is admissible in evidence without proof of its due execution or genuineness; a private writing needs proof of its due execution and authenticity before it is admitted in evidence inany proceeding;(b) Persons bound: A public document binds third parties or strangers to the document andmay be used in evidence for or against the saidpersons; private documents on the other hand bind only the parties who executed them and their privies insofar as the due execution and date of the document is concerned. (Read this with Article 1311 NCC);(c) Validity of certain transactions: There are instances where the law requires form for their validity or enforceability (see Article 1356 and 1403, NCC), otherwise they may not be considered valid or enforceable by action.
18. Authenticity and due execution of a private writingThe authenticity and due execution of a private writing may be established by: