What does "Get all you can, can all you get, sit on the can." mean? It seems that Google can't help me with this one.
Could you also explain its origin and how it is related to the meaning?
The meaning may depend on whether the person hearing it speaks British or American English. Being British I thought the third use of 'can' referred back to the second, but switching from verb to noun, giving the meaning:
1) Get everything you are able to get
2) 'Can' your gains (keep/preserve them, put them away)
3) Sit on that can (that is, guard your gains so no-one else shares them).
I didn't immediately understand 'can' as 'toilet' as the use is rare in Britain.
There is a page though from a blog by an (American?) HR consultant dated December 2011 and headed 'Get all you can. Can all you get. Sit on the lid.' which suggests it may also have had the same meaning to Americans once. http://www.thebuzzonhr.com/2011/12/21/howto_setprioritiesanddelegate/
Get all you can
Can is a modal verb: “Obtain all that you are able to obtain”
Can all you get
Can is a transitive verb.
2.1 reject as inadequate
“Reject as inadequate all that you obtain”
Sit on the can
Can is a noun.
3 (the can) North American • informal the toilet
“Sit on the toilet”
You’re here to consume and enjoy. Get all you can. Can all you get. Sit on the can. That’s why you’re here. That’s the only thing that matters.
It advocates a hedonistic lifestyle of selfish consumption, very much in the style of “Eat, drink and be merry” (the end result of eating and drinking requires “sitting on the can”). This is borne out in another Google result which attributes the original to the Methodist minister John Wesley.
John Wesley once said, “Get all you can, save all you can, give all you can.” The equivalent of that philosophy in our culture seems to be, “Get all you can, can all you get, sit on the can and poison the rest.” We live in a culture of greed. We always want more.
I know this word play in this form: Eat what you can, and can what you don't. As "can" in the second part has no infinitive it must be a normal verb. to can sth meaning to conserve in tins. This normal verb can and the noun can (tin) is connected with German Kanne, originally Latin canna, a small container without lid for liquids.
It's simple play on words -- three entirely different meanings of the word "can".
"Get all you can" means to acquire as much as you are able to.
"Can all you get" means to place in a container (jar or "tin can") all of your acquisitions.
"Sit on the can", in US speech, means to sit on the toilet and simply do nothing (besides possibly "making a deposit" there). The expression is sometimes used to suggest being intentionally oblivious to what's going on around you. The fact that this might also be taken to mean sitting on the container of the second sentence, so that nothing is done with you acquisitions, is a sort of "bonus" meaning -- it gives the play on words an intellectual twist.
I know "on the can" is an old fashioned term for going to the toilet.
"Get all you can, can all you get, and sit on the can" is indeed is a reference to greed.
"Get all you can": acquire everything that you are able to in anyway you can get it.
"Can all you get": keep it stored or tucked away as in a tin can, coffee can, or a mason jar as people sometimes do.
"Sit on your can": protect it all. Imagine all of the money or goods you have ever acquired stored in one large can and you are sitting on the lid protecting anything or anyone from taking any of it.
It's greed pure and simple, I have heard it refer to a desire to get ahead but that is not a fitting view of this saying.