rationalskepticism.org

Thomas, I'm afraid you don't understand logic. In logic, two assumptions are made. The assumptions may not necessarily be true in a give syllogism. I am saying that the conclusion from these two premises must be coherent with the first two assumptions. So the question now is WHAT is moral (that's moral philosophy for you). These two assumptions allow a person to explain whether any action sone by anybody is moral or not moral. This is called INTERNAL CONSISTENCY, and refers to when a theory is able to discern conclusions based on assumptions. My assertion is that Islam is the only moral philosophy that has internal consistency.

Regarding EXTERNAL CONSISTENCY, which refers to whether or not something is actually moral (if morality exists, that it), Islam is the only moral philosophy whose premises are not illogical. For instance, while one premise of Christianity may perhaps be profession in belief of the trinity, by deconstructing the trinity's assertions, one can disprove the external consistency right off the bat and discard it. Likewise, if a philosophy holds as a premise that the universe is eternal, one can deconstruct the external consistency of an argument by proving it is not.

While ignoring the issue of external consistency is in the interest of sparing our time, I will assert this: Islam is the only logical moral philosophy because it is the only one that can deduce whether something is moral based on two assumptions. You can counter that by providing a philosophy that does.