Access to postgresql query optimizer output

[Seref Arikan <serefarikan@xxxxxxxxxxxxxxxxxxxxx>]

Greetings, 
I keep seeing statements like "Postgresql optimizer rewrites this query as...." What I'm curious about is, is there a way to obtain SQL form of the re-written queries somewhere in the chain of query evaluation? It does not make a lot sense to generate sql again, but it would help a lot to see  the queries in their  rewritten form.

Kind regards
Seref