>>48
>>49
>Why should you doubt them? 
Reason leads me to doubt. If inquiry means going all the way then way not go all the way? 
It is our belief that sun is going to rise up in the morning. You can say how? I would say one can die. How humans look at the world isn't objective there are reptiles who view things in a funky way so why your version of viewing those things is any more valid than reptiles? 

This infinite chain of why lead to extremely out there positions. You can arrive at epistemological nihilism. What if everything was created in the last second? Or Demon hypothesis that what if a demon is deceiving you right now to not view things totally differently? Are you some kind of brain in a vat? You can deny all of this by saying "I don't care" but why you don't care? "Just because". 

I don't know. You just have to blindly accept 1+1=2, there's no means of proving it. Why water is H2O? "Just because"

There are limits to knowledge. I don't think that we'll ever be able to figure out truth. To know the truth you have to stand outside of limits. That's no human can do.