I'd argue they are two sides of the same coin.
And I'll refer to the amazing Punjabi sufi poet Bulleh Shah to make this point.
It is the search for the most parsimonious theory to explain observed behavior.
The ultimate example is the elusive search for the "theory of everything" in Physics - that one single conceptual framework that is able to explain the entire universe.
He defines spirituality not as passing judgement on others, or worse, as any claim to self-righteousness. But as annihilation of the self or `nafs'.