Revealed preference

[Asd1995]

If an individual prefers X to Y and exhausts all his income, can we conclude px>py?

Te idea of revealed preference says

px(1) + py(0) >px(0)+py(1)

Or px>py

This doesn't make rational sense, one does not necessarily prefer costly goods over cheaper goods.

Where am I going wrong?

Edit: I've sorted my misunderstanding.

[Algaeconomics]

You've sorted it out?

[Asd1995]

Yes, wht we can say if if Y is preferred over x in some case, then x will not be affordable

px>py (necessary condition for consumer to buy y)

[Algaeconomics]

Nahi toh.
I dont think Px/py >1 is a necessary condition.

[AmyDunne]

If the Utility function is such that x is preferred to y , then in any scenario if y is consumed rather than x it has to be that px>py, Otherwise the consumer would always go for x in the first place and not y.

Does this make sense?

[Asd1995]

So if you prefer some commodity to another, and it is cheaper, would you buy the one you don't prefer?

[Asd1995]

Yes, that is exactly what I mentioned 2 posts above. Thanks for the clarification.