Nullbyte
But we don’t know if hormone X is a cause of tremor or not. We are assuming that just because they are present together
For example if you say "yesterday Henry drank cold water and he got sick today so cold water must have caused the sickness".
But here we are assuming that nothing else caused the sickness
We are not. This assumption is specious because it is possible that drinking cold water led to 'infection X' and it is 'infection X' that caused the sickness. In other words, 'infection X' induces sickness, and 'infection X' could get triggered by various causes, one of the causes being drinking cold water. The conclusion in the question I have shared is this: When hormone X exceeds normal concentrations, tremors are induced. So, hormone X's exceeding normal concentrations could lead to a hormonal imbalance, and another hormone, hormone Y, may get impacted, leading to tremors. So, my question to you is this: Why should no other hormone other than X that causes tremors be an assumption?