And I am wondering what the meaning of "AS" in this sentence is?
Allan Bloom in his famous book The Closing of the American Mind (1987), drawing on Max Weber, calls the “fundamental issue”of our time “the relation between reason, or science, and the human good.”I would say that in the university today the most obvious issue, reflecting directly the fundamental issue, is the relation between science and non-science. Let’s start from non-science as the residue of what is not science.

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Let’s start from non-science as the residue of what is not science.

I thought that this sentence shows the definition of "non-science." Is it right?
And I am wondering what the meaning of "AS" in this sentence is?

Please help me!
Thanks!

Question

And I am wondering what the meaning of "AS" in this sentence is?
Allan Bloom in his famous book The Closing of the American Mind (1987), drawing on Max Weber, calls the “fundamental issue”of our time “the relation between reason, or science, and the human good.”I would say that in the university today the most obvious issue, reflecting directly the fundamental issue, is the relation between science and non-science. Let’s start from non-science as the residue of what is not science.

--
Let’s start from non-science as the residue of what is not science.

I thought that this sentence shows the definition of "non-science." Is it right?
And I am wondering what the meaning of "AS" in this sentence is?

Please help me!
Thanks!

Answer

As is mostly used to compare something. Ex: I am not as smart AS my brother.

But it can also be used to redefine something. In this case, They are defining non-science as a residue.

I'm not fond of how they worded the sentence myself.

But to help you understand the concept, here is another example.

"Lets look at learning a language as a tool to help us"
We are not comparing anything. What we are doing is using AS to redefine (learning a language)

learning a language = a tool to help us