In my 1980’s boyhood in a southern town of Saudi Arabia I made a skeptical inquiry : I covered a small piece of meat with grass to feed it to sheep but they avoided it!

And i think it’s fit nicely with what Carl Sagan said :

“Science is more than a body of knowledge
It's a way of thinking
A way of skeptically interrogating the universe“

Today, in cosmology I try to learn more about what Stephen Hawking had said :

“ We observe that distant galaxies are moving away from us
They must have been closer together in the past

It was the beginning of the universe
And of time itself
Anything that happened before the big bang
Could not affect what happened after”

What are the assumptions?