Assumption : An assumption is an unsaid creation which gives backbone to the conclusion. Both creation and assumption are indisputable facts but creation is not clearly mentioned and hence assumption needs to be read carefully. Rather assumption is usually taken for granted in the setting of a statement.
In other words any unseen part of the statement is known as an assumption. This is basically the hidden part of the statement which is assumed and taken for granted or Things which are not clearly stated in the statement, but is a part of it. Under these problems if something is said by author, that doesn’t mean it is written clearly. Lot of unsaid things are there which are not mentioned in the statement. The things which are not mentioned are taken for granted, and can be defined as an assumption.
For Example : ‘All M.B.A students are happy when they get latest gadgets. Rishi will be excited when he will receive the latest tablet.’ In this, the assumption is that Rishi is a M.B.A student. Without assuming this, no sense will be there in the argument.