Postgresql - Having trouble performing left joins on multiple tables

I'm in the process of moving some Mysql queries over to Postgresql and I ran across this one that doesn't work.

select (tons of stuff)
from trip_publication 

left join trip_collection AS "tc" on
tc.id = tp.collection_id

left join 
            trip_author ta1, (dies here)
            trip_person tp1,
            trip_institution tai1,
            trip_location tail1,
            trip_rank tr1
    ON
            tp.id = ta1.publication_id 
            AND tp1.id = ta1.person_id 
            AND ta1.order = 1 
            AND tai1.id = ta1.institution_id 
            AND tail1.id = tai1.location_id 
            AND ta1.rank_id = tr1.id

The query seems to be dying on the "trip_author ta1" line, where I marked it above. The actual error message is:

   syntax error at or near ","
   LINE 77:   (trip_author ta1, trip_person tp1, ... 

I went through the docs, and it seems to be correct. What exactly am I doing wrong here? Any feedback would be much appreciated.