Actually, I think society would be better off if more people were consuming regular doses of lithium! Although you are right that I wouldn't support treating our water with it. However, if the evidence and scientific consensus supported the use of lithium in the water, I would have to seriously reevaluate my position on it. Because I'm not an expert, and I'm not qualified to contradict the science. I have to rely on the empirical evidence, and relevant subject-matter expert consensus to base my beliefs on.

If the the weight of the evidence, and scientific consensus shows that flouridation is actually more harmful than helpful, and that its use is no longer justifiable, I would defer to the consensus and support ending flouridation. Again, because I'm not an expert, or in a position to declare that the scientific consensus is wrong, I have to go with the current scientific position. But I also understand and accept that not everyone views it the way I do, and I respect anyone who presents their views respectfully, and with reason.