At Socratic Seminars International, we promote dialogue and NOT debate in our Socratic Seminars. When a Socratic Seminar is rich in dialogue, participants reveal assumptions for examination and reevaluation. My experience in introducing and practicing dialogue with students and adults has made me realize that many of us are not so sure what the relationship is between an  assumption and an inference. Richard Paul and Linda Elder of the Center for Critical Thinking are internationally recognized authorities on critical thinking and published a short article on this subject that is clear and illuminating. It is titled Distinguishing Between Inferences and Assumptions. Below I have summarized some key points for your consideration.

Inferences and Assumptions

1. Inference: An inference is a step of the mind, an intellectual act by which one concludes that something is true in light of something else being true, or seeming to be true. If you come at me with a knife in your hand, I probably would infer that you mean to do me harm. Inferences can be accurate or inaccurate, logical or illogical, justified or unjustified.
2. Assumption: An assumption is something we take for granted or presuppose. Usually it is something we previously learned and do not question. It is part of our system of beliefs. We assume our beliefs to be true and use them to interpret the world about us. If we believe that it is dangerous to walk late at night in big cities and we are staying in Chicago, we will infer that it is dangerous to go for a walk late at night. We take for granted our belief that it is dangerous to walk late at night in big cities. If our belief is a sound one, our assumption is sound. If our belief is not sound, our assumption is not sound. Beliefs, and hence assumptions, can be unjustified or justified, depending upon whether we do or do not have good reasons for them. Consider this example: “I heard a scratch at the door. I got up to let the cat in.” My inference was based on the assumption (my prior belief) that only the cat makes that noise, and that he makes it only when he wants to be let in.

We see dark clouds and infer rain.

We hear the door slam and infer that someone has arrived.

We see a frowning face and infer that the person is upset.

If our friend is late, we infer that she is being inconsiderate.

We meet a tall guy and infer that he is good at basketball.

Often different people make different inferences because they bring to situations different viewpoints. They see the data differently. To put it another way, they make different assumptions about what they see.

 This page was edited and adapted from the book, Critical Thinking: Tools for Taking Charge of Your Learning and Your Life, by Richard Paul and Linda Elder.

We at Socratic Seminars International believe thoughtfulness starts with looking closely at the assumptions and inferences made by ourselves and those around us, in and out of Socratic Seminars.