It is easier to convince people to believe in simpler theories than more complex ones.

Simpler theories require less evidence to support than more complex ones do$,$ and since it is very difficult to support moral theories with evidence, simpler theories are preferable to more complex ones.

Simpler theories are not only easier to comprehend, but they are also more likely to be true; the number of conditions that need to come together in the right kind of way to make the theory true is lower than the number of conditions necessary for a more complex theory to be true.

Simpler theories do not require arguments to support and more complex theories do$.$lol