 Goldberg (2015) argues that the norm of assertion hypothesis can explain why we have a (pro tanto) epistemic entitlement believe what we are told. He identifies some requirements that are needed to meet this desideratum. One is that the norm of assertion is robustly epistemic, and strong enough to warrant testimonial belief (2015: 96). Another is that it must be common knowledge between speaker and hearer that the speaker’s assertion is subject to this norm. A further requirement (2015: 8) is that the speaker authorizes the hearer to defer back to the speaker the responsibility of meeting challenges to the assertion. Together, these assumptions should be able to explain why beliefs based on testimony are pro tanto justified.