What does 'substantiate' signify in a discussion?

The term 'substantiate' signifies the act of providing proof or validation for a claim or argument in a discussion. When someone substantiates a point, they support it with evidence, examples, or reasons that lend credibility and weight to the assertion being made. This is crucial in any logical discourse because it strengthens the argument and allows others to evaluate its validity based on concrete information. In contrast, rejecting an argument does not involve providing proof but rather dismissing the validity of the claims made. Ignoring evidence signifies a failure to engage with the points presented, while expressing an opinion without support lacks the foundational backing that substantiation provides. Hence, the choice that accurately reflects the meaning of 'substantiate' is to provide proof or validation.