He means We (you, me, other humans) experience time passing consciously and sequentially. We are on the inside of a 4 dimensional bulk. We are traveling throug

He means We (you, me, other humans) experience time passing consciously and sequentially. We are on the inside of a 4 dimensional bulk. We are traveling through the temporal dimension. As opposed to outside of it looking in. In which case we would "see" past, present, and future simultaneously.