the first two resolutions discussed above (the "simple resolution" and the "bayesian resolution") correspond to two possible interpretations of what is going on in step 6 of the argument. they both assume that step 6 indeed is "the bad step". but the description in step 6 is ambiguous. is the author after the unconditional (overall) expectation value of what is in envelope b (perhaps - conditional on the smaller amount, "x"), or is he after the conditional expectation of what is in envelope b, given any possible amount "a" which might be in envelope a? thus, there are two main interpretations of the intention of the composer of the paradoxical argument for switching, and two main resolutions.