physicists and their task i task of providing a comprehensive picture of what there is:

 Are   there are such things as quarks, for instance, a physicist has better explain what they are, otherwise her existential statement would be unintelligible. Why should it be different in math? More importantly, why should it be different in philosophy? 

At most, one could point out that spelling out her ontological credo does not exhaust the philosophical task of providing a comprehensive picture of what there is: a good philosopher should complete the picture by also spelling out the underlying metaphysics.

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