Do you notice that some people are certain when they couldn’t possibly be certain? They know what is going to happen in the future and tell you with confidence. It’s probably coming from a need to show they are smart because they can predict the future. It would be unwise to contradict them as they may become more certain. I suspect that nothing is certain except death. Taxes used to be certain but this may not be true for everyone, I’m told. If someone is 100% certain it is tempting to ask them what will happen if they are wrong. Don’t do it. No investments are certain to prosper including any involving bitcoin.
My suggestion is to listen to people who are certain but be wary of their advice. Understand that they want to prove something to you about their superior ability to know the future. Accept what they say but don’t act on their advice. If they tell you they are certain that they don’t have the virus, treat them as if they do. There is one other certainty. The present moment, the now. You can be certain that you are reading this. Certainty slips a little when you move into the future in your mind.