When language used in a document is plain in itself, and when it applies accurately to existing facts, evidence may not begiven to show that it was not meant to apply to such facts.
Illustration
A sells to B, by deed, "my estate at Rampur containing 100 bighas". A has an estate at Rampur containing 100 bighas. Evidence maynot be given of the fact that the estate meant to be sold was one situated at a different place and of a different size.