Yet there is no stronger philosophical argument today to look for explanations in intelligent aliens than there was 500 years ago.
There is, and they didn't decide upon "intelligent aliens" 500 years ago, they decided upon "Gods", two very different concepts. Confusing them will shut your eyes to the possibility of SI influence on natural laws.
The stronger philosophical argument comes from our newfound knowledge of the structure and composition of the universe. We are on a planet. We more than likely arose from this planet alone. Therefore it is probably possible in this universe for lifeforms to arise directly from the presence of a suitable planet. There are a squillion and one planets. Fill in the rest yourself.
What I am saying is that they didn't have this knowledge from which to make philosophical inferences 500 years ago, in fact, most religions would set out that Humans are the only species as advanced as we are in the whole of eternity, and ours is the only planet - minus the God(s). Therefore, reaching decisions concerning Gods was a prerequisite. Not so now. We can actually postulate the existence of SI's based upon real scientifically collected data as in the the simple logic trail above.
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