I read somewhere that the pyramid structure was quite common because it imitated nature and was found to be more solid than any other structure. Hence, copying man made building styles would be less likely than taking nature's lead. i.e. sand piles, mountains, ant nests etc.
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I'm not blind to your facial expression - but it may take me a few minutes to comprehend it.
A smile is not always a smile.
A frown is not always a frown.
And a blank look rarely means a blank mind.