I think one lobe is working against the other. Here's a typical conversation:
Left Lobe: The mortgage and bills are due this week.
Right Lobe: If I just had that extra piece of diving gear, we could do some cool things.
Left Lobe: Like What?
Right Lobe: Head to the quarry with our new dive light and simulate wreck diving on the cabin cruiser we swam around last week.
Left Lobe: Maybe next month.
Right Lobe: But were on a revolving checking account.
Left Lobe: Revolving?
Right Lobe: Yeah. If you buy it then, you'll save for it now. But if you buy it now, we can save for it then. In the end, it totals out the same.
Left Lobe: Are you sure? We wont have enough to pay our bills this month.
Right Lobe: That's next month. Remember, revolving bills.
Left Lobe: Oh yeah.
Right Lobe: Trust me.
Unbridled Mouth: Ok. Salesperson, i'll take that cool Tec II dive light. Yes the really expensive one!
Salesperson: You made an excellent choice sir.
Unfed Ego: Why thank you. Yes, I feel I did.
(on the way home with my new purchase)
Right Lobe: Did you see that cool dive knife behind the other counter?
Left Lobe: What did I just do again?
Right Lobe: Huh? Your asking me?
...