Post-flop odds

[themflags]

What are the proper odds to consider post-flop, when thinking about betting or calling? I know the basic odds for making your hand on the turn or river. But isn't it true that if the turn doesn't make your hand, then the odds have shrunk (while the bets has doubled)? It would seem that you would frequently fold if the turn does not help you. If this is the case, then why would you consider turn+river odds when you may have no intention of paying to see a river card?

It seems that considering turn+river odds would inflate (beyond reasonableness) your justification for paying to see a turn card, unless you were willing to pay to see both cards, and that you knew this before seeing either card.

Thoughts?