It is the reality, stupid.
Entering the realm of questioning reality is like trying to dig for gold in your backyard. Dig and dig, we find crumbs. CRUMBS. Nothing more, nothing less. Unfortunately, all we need are crumbs to make us addicted to our primary objects, gold.
So, what if we try digging for reality? Do we dig and dig and just find mere crumbs? Yes. Reality if thought about thoroughly enough, is indefatigable. In the end, are we actually searching for the right thing? But surely, the 'right' thing does not really exist.
And so we move on the existence. Related to philosophy now, you say? Yes, and there lies the problem. No, philosophy is not the problem. Neither is it the mind. More like the thinking is somewhat problematic. Are human beings really born to think? Yes. Are we meant to think about something meaningful? No. I think.
Again, does it matter? Before we can even figure out whether what we are thinking so hardly matters to us or our environment, we might soon face nothingness. We hit a block in our minds that cannot be defined, we just can tell whether we are doing things 'right'.