We need to look because it is the next hill to look over.
What would have happened if the early explorers of planet Earth had said we can't prove that other life exists on other land masses or even if there are other land masses existing therefore we should not go

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And to early humanity before reliable shipping the other continents would have been no different than we consider travel to other star systems it is the dreaming which pushed those early explores to develop new ships as an example of new technology without imagination we will go nowhere.
The technology to do these things will come just as modern shipping enabled the discovery of and mapping and inhabiting of the Earth so shall we make the next leap of expansion into our Galaxy so we should be preparing for that exploration and simply wait to discover what is there but never stop dreaming as it is dreams that propel us forever onward and upward


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