Logical speculation is absolutely essential in the scientific field because it creates testable hypotheses. If there are several lines of evidence pointing towards a conclusion, then it makes sense to speculate about that conclusion even without direct investigation. Hopefully that direct investigation comes, but we can’t wait for that to happen because it would stagnate the scientific field as a whole.
Example: long-term effects of a low-fiber or fiber-free diet in intestinal health, particularly when combined with a high intake of protein. There are no long-term human studies looking at this. However, we have mountains of evidence in animals and test tubes, as well as short-term studies in humans, that provide insight for how things in humans might play out. Over time, beneficial butyrate-producing bacteria become extinct, causing long-term dysbiosis and an intolerance for carbohydrate fibers. Levels of intestinal inflammation increase and colorectal cancer becomes grossly more likely.
This speculation could be flat-out wrong and direct investigation can answer that, but at this moment there is no reason to believe that this speculation is wrong because that is where the current base of knowledge points.
But, you can’t always logically speculate due to the novelty of a situation and the risks involved with being wrong. A lot of people are giving recommendations specific to the novel COVID with little to no background in virology combined with little to no research on this strain of virus.
That’s a horrible combination because it turns any potential for logical speculation into just plain speculation, and there’s a huge difference there because logical speculation requires a fundamental understanding of the topic and a base of indirect research to work from.
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