An assumption is an idea or premise that is accepted as true without much evidence or verification. This isn't necessarily a bad thing as assumptions can be used as a starting point for reasoning, decision-making or strategies. However, unstated assumptions can also resemble faulty thinking such that they can cause a variety of failures. The following are the key things to know about assumptions.
Assumptions are Unverified Beliefs
Assumptions are held as true without requiring evidence or proof. For example, assuming that your new coworkers are trustworthy by default.
Assumptions are Efficient
In a complex environment it is not always possible to constantly verify all of your ideas and premises. Assumptions may be good enough and require little or no work such that they can be efficient. For example, assuming that your competitor will be launching new products soon without any actual competitive analysis.
Assumptions Can Be Conscious
It is possible to recognize that a belief you hold is nothing more than an assumption such that you don't place much weight in it. For example, assuming that people will have 2-3 drinks each at a dinner party you are planning.
Assumptions Can Be Unconscious
It is very common to form ideas without any verification or evidence and without recognizing that the idea is largely baseless. For example, assuming your neighbor is a bad person because they seem quiet.
Assumptions Influence Perception
Assumptions influence how you think and feel about things. For example, if you assume your neighbor is in a bad mood because they didn't smile, you may begin to perceive them negatively.
Assumptions Can Be Correct or Incorrect
Assumptions aren't necessarily correct and they aren't necessarily incorrect. Normally, they are your best guess so they are hopefully correct more often than not.
Assumptions Can be Shared
Assumptions aren't just a personal thing and can be adopted by a society, culture or group. For example, a culture that assumes people value freedom.
Assumptions Can be Stated
It is a good idea to document assumptions, particularly when working collaboratively with others. For example, a construction project that assumes permits will be received on time.
Assumptions Can be Foundational
Many of our most basic beliefs are assumptions. For example, the belief that time as value.
Assumptions Can be Principles
Principles are something important that you hold to be true in order to make key moral, life or business decisions. For example, the principle that you must take responsibility for yourself.
Assumptions Can Be Simplifications
Assumptions can be simplifications that you adopt without any evidence. For example, assuming that religious people must be conservative.
Assumptions Can Be Unfair
Naturally, if you are forming and using ideas that aren't based on evidence this can be quite unfair. For example, assuming that know what someone is thinking when you really can't know.
Assumptions are Subject to Confirmation Bias
People tend to look for evidence to support assumptions and may ignore evidence that contradicts their assumptions. For example, if you assume that people in sports cars drive recklessly you may look for examples of this on the road.
Assumptions Can Lead to Overconfidence
Assumptions can create a false sense of certainty whereby you have high conviction in beliefs that are flawed or fully untrue.
Assumptions Can Create Biases
Assumptions are a basis for a wide range of biases. For example, assuming older people are slow to adapt such that you avoid hiring them.
Assumptions Can Create Interpersonal Conflict
Assumptions are a common source of interpersonal conflict. For example, assuming that your husband will pick up milk after work without asking him and then being annoyed when he doesn't.
Assumptions Can Be Managed
It is possible to try to prevent others from making assumptions by communicating what you will and will not do. This is a basic social skill that is also important to management. For example, a project that clearly states out-of-scope items that are essentially a list of things the project will not deliver.
Summary
An assumption is something that you hold to be true without evidence. This is essentially a way to deal with uncertainty that can be efficient and useful but is also prone to a wide range of problems such as causing failure, disputes and unfairness.
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Assumptions
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