Burden of Proof
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"Burden of Proof" is the obligation that is normally attributed to a speaker or writer to provide credible or plausible reasons for his or her major claims. The burden of proof in any particular argument is "heavier" or "lighter" depending upon how much may be presumed and how ambitious the thesis or conclusion is. There is a higher burden of proof in showing that there are aliens among us than showing that that antibiotics work. Once a burden of proof is met, even tentatively, then the burden shifts to those who dispute the reasoning offered. Of course in a contentious argument, there will be differences of opinion about whether a burden of proof has been met.
The word "proof" in the phrase "burden of proof" may cause some confusion. In arguments about the kinds of complex topics that interest most people, there is rarely anything that could count as irrefutable "proof." From a practical standpoint, what happens in these discussions is that participants offer support for a claim that others regard as legitimate or at least minimally persuasive. Once someone does that, their burden of proof obligation is at least temporarily discharged. It is then up to others to offer stronger reasons or a new way of thinking about the issue such that the burden shifts back to those who would disagree. Burden of proof and presumption are related because one way to shift the burden of proof is to undermine the presumption of the previous argument. This strategy is like saying to someone, "I guess you gave good reasons for your claim as long as you presume X, but without that presumption, your reasons do not support your claim." The main points to remember about "Burden of Proof" are:
- Burden of proof is an obligation to provide reasons for claims in a reflective discussion;
- Burden of proof shifts as more compelling reasons are offered for different claims; and
- Burden of proof in a discussion depends upon what is already presumed. One way to shift burden of proof is to undermine or question a presumption.
