Implicit and Explicit Assumptions

“An assumption is an assertion about some characteristic of the future that underlies the current operations or plans of an organization�

There are multiple types of assumptions. The most known derivation is between implicit and explicit assumptions. Another classification used in ABP is the derivation between primary and secondary assumptions. This latter categorization is discussed in the Critical assumption planning Wiki. The two classifications are not mutually exclusive; this means that an assumption can be both an explicit and a primary assumption, while another assumption can be implicitly derived.

Explicit assumptions are assumptions of which the intention that is fully revealed or expressed without vagueness, implication or ambiguity. (Based on the m-w.com definition of explicit). However, as you can read in the next section “Primary and Derivate Assumptions�, explicit statements in a plan often have underlying (implicit) assumptions. Explicit assumptions are often not hard to find, since they are explicitly stated in the business plan. Examples of parts in the business plan full of explicit assumptions are the financial forecast and the business system and organization.

Implicit assumptions are assumptions that are capable of being understood from something else though they are not expressed. (Based on the m-w.com definition of implicit). The problem is that some important implicit assumptions in a plan go undetected. And if no precautions are taken for a scenario where implicit assumptions prove to be wrong, this might lead to unpleasant surprises. Callout 1 lists ten dangerous implicit assumptions often made in business plans. It is important to identify both the implicit and explicit assumptions made in plan.