Hypothesis:
When rates are high people will spend less (save more).
The inverse is also true

Test:
some very smart nerds test tis hypothesis again and again, bylooking at history, By comparing two states, two countries etc…

Result:
People are always gonna waste money on stupid crap, but some policies make them spend more some make them spend less. Since many people (incorrectly) claim “spending”= “the economy” adopting policies that grow spending also grows the economy.