If you disagree, then suppose to be true whatever you want to suppose to be true.

Would you like to live?  Then eat.  You have to eat to live.  Oh yeah, another thing ... it has to be food.  Eating food gives life.  If it's not food that you're consuming then you're not really eating.  If it's, say ...  foam rubber, you can chew it up and swallow it and your system will make an attempt to digest it but you will get no life from it.  It may in fact cause you to die.  So I'm going to say that if when you eat it, it gives you life, then it's food and if it's not food, then you are not really eating ...because it doesn't give you life. Eating food gives life.  

Another very useful, necessary and even essential act for the sustaining of human life is that of breathing.  You must breath air to live.  And once again I think it's important to stress that it really must be air that is breathed in order to live. You can suck carbon dioxide into your lungs and force it back out with your diaphragm but only a time or two before you start to lose consciousness.    I tried to breath some water once when I was a kid and I could tell right away that it wasn't going to work.  So I'm going to say that when you suck air in your lungs and get life from it, then you're breathing but if it's not air then you are not really breathing ...because it doesn't give you life. Breathing air gives life.

I've heard people say "I'll believe what I want to believe."  This is a nonsense statement and I'm taking the time to explain eating and breathing in order to show that believing  seems to work analogously to them.   Believing truth gives life.  Do you want to live?  Then believe.  You must believe to get life and it has to be truth to be believed.  You can take lies into your head and suppose them to be true but you'll get no life from them.  I have to say that if it's not truth,  then it can't even be believed because it's the believing of truth that gives life.  If you disagree then suppose to be true whatever you want to suppose to be true but don't say you'll believe what you want to believe  because I don't think it can be done.

My apologies to George MacDonald.