*quality

Boosting this quality contribution up in the Hot Listing - declared quality by Gratefulmom.

Interesting idea, but I have two main problems with this premise.

Firstly, it's not like we've got a lot of resources invested in the search. If I have a few people people to search a large forest for a particular type of tree, I'm going to use large scale searches looking for big obvious examples... I'm not going to do a sweep search to look at every tree.

Secondly, it doesn't take into account what's required for intelligent life to develop. He picked an example of a sports team - Manchester United - but didn't take into account that the best players (which I suggest is equivalent to intelligence) are all in the premier league, which comprises 20 teams. There are hundreds of other teams out there that would hardly blip on a skillometer (which I suggest is equivalent to a mind gauge).

OK, that second example got a little stretched and frankly weird, but it's key that we're looking for intelligent life, not all life, because intelligent life gives off more signals. Probably. No one really knows.

Why does he say that we have a "high population of humans" on this planet compared to another populated planet, and therefore aliens will be larger than us? The guy knows we have one data point, so how is he able to establish our population size relative to an alien population? And why should they be larger than us - surely environment and social factors dictate this. For example Earth was home to dinosaurs (some of which were MUCH larger than us) and now it's home to humans? Furthermore, the size of the brain does not necessarily dictate how intelligent a being is, and with a greater body size it's more likely the being will have to spend more time gathering food and less time developing society. The larger the body, the less responsive the extremities become, the more energy and brainpower is required to regulate all of the body's functions?

But besides all of this, he actually opens the video by asking why we are looking for life like ours when life could be any kind of weird and wonderful thing. It could be made in a way that we had no idea could happen, in a place we thought incompatible with life. Why then are we to assume that larger aliens on smaller planets will be more intelligent? Or that the light from stars encourages growth? Why should alien creatures follow our social norms of gathering around popular landmarks - be they football teams or countries? Why are any of these human-based assumptions relevant when your argument is that they don't have to be like humans in any way?

At the end of the day, the best evidence we have about life indicates to us that it should be on an Earth-like planet. Why would we waste our limited time and resources looking elsewhere, especially when we have no idea what the evidence we're looking for might look like? This is a thoroughly uncompelling argument.