Either way, we’re all in this vessel together
Literally: all – “sort of thing” – one – body
Alternately: Disparate things mixing together to form a harmonious or unified whole. A workable sum of parts. The ideal of American society.
Notes: The 渾 may be replaced with homophone 混, “mix.” The compound may also be followed by ～となる (to naru), “to become (a complete whole).” 渾然一体となる can also simply mean “to be joined together.”
This compound comes to us from the seventh chaper of the Huainanzi (『淮南子』), which we’ve seen before. Note also that things becoming 一体 is a recurring theme in yojijukugo.