Logic is a systematic description of the irreducible minimum relationships between propositions for a coherent, self-consistent reasoning process, discussion, discourse, whatever you want to call it, about the content of any set of propositions about reality.
It is the starting point for coherent discourse.
The rules of logic start from the 'assumption' that there exist sets of propositions, statements about reality that cannot all simultaneously be true, that describe distinguishable, different possible attributes, events, relationships between entities, ie that there is structure to reality, not just a blur of every everything posssible existing and happening at once and/or at pure
This is fundamental.
To insist that this somehow can only be the case if there is some grander entity within which such a structure can exist explains absolutely nothing, merely opening the way to the worst sort of infinite regress, requiring ever grander entities within which any given entity must exist, therefore such a proposal is essentially self-refuting.
Rather pursue the more fruitful chain of 'infinite' regress, where each complex proposition of logic, or the elaborations of logical reasoning, ie mathematics in all its forms, is shown to be derived from simpler, more fundamental theorems, till we arrive at the most elementary.
Analogous to following 'cause and effect' chains back, where any given 'effect' can be seen as being initiated by a set of one or more 'causes' whic may well be much more elementary and lesser that the effect triggered, so that the 'ultimate cause' need only be a set of infinitesimal 'twitches' in the fabric of reality.
As long as all the identifiable cause-effect links form, on average, a geometrically decreasing sequence in duration and energy, as we trace back, then even a theoretically infinite sequence will total to a finite duration and energy, a point that the Greek philosophers totally failed to get there minds around, as with Xeno's famous paradoxes, which are totally resolved by later mathematics, such as those dealing with infinite series and calculus.
So once you eliminate the assumption that 'cause' must always be greater than 'effect', most if not all traditional arguments for 'God' vanish in a puff of logic, as Douglas Adams once said. Just think of the final snowflake that triggers the avalanche...
'God' and all such ideas are part of a lesser, derivative reality, the world of speculative ideas which is totally dependent on our own minds, which in turn are parasitic on the world of nature.
Quote from Bob Spence on the BAMG message boards.
Is truth knowable - only if you assume it is ;).