How does one respond to this argument?It's long but an interesting read. Thanks :)

[Neo-Scholastic]

The great thing about Occam's Razor (Among competing hypotheses, the one with the fewest assumptions should be selected.)  and Hitchens Razor (That which can be asserted without evidence can be dismissed without evidence)

You are applying only part of Occam's Razor. Among competing hypotheses that each explains all the relevant phenomena, the one with the fewest assumptions should be preferred. First, Occam's Razor is merely an epistomological guide. You cannot disprove a hypothesis using it. The hypothesis with greater number of assumptions could still be the correct one, even while adopting the lesser seems more reasonable. Secondly, it is a matter of debate whether the naturalist stance adequately accounts for all the things needed to be explained. Here, in the interest of time, I must only refer to the Principle of Sufficient Reason.

Hitchen's Razor (or was it Sagan's) is just plain wrong. No type of inquiry would be possible without asserting first principles that do not require any prior evidence.