A lot of people seem to be so ready to read a different article that they aren&#x27;t noticing what this one is about. This is not an article about &quot;If a given planet holds life, how could we detect it?&quot; This article is about &quot;If a given signal is detected from a planet, what characteristics of the signal would allow us to conclude it could only be from life?&quot; It&#x27;s a completely different question. It&#x27;s not about avoiding false negatives, it&#x27;s about avoiding false positives. It is obvious that a planet could hold life, and we could fail to detect it; we&#x27;re still arguing about whether <i>Mars</i> has or had life, after all! And we&#x27;ve actually landed probes on it.