It comes down to you believing something is real because someone writes or states it is real.
...and you do this multiple times every day, in a variety of different ways. You're just cherry-picking something (RE) to disagree with and pick at.
Examples;
I looked at the news, and there were a bunch of dumb quotes from Trump. Did he really say them? Should I check, or do I take the news outlets at their word? Do I need to look for video and audio recordings of them all to make sure?
I was in the supermarket, and there's a big skull-and-crossbones graphic on the cleaning products, advising that they are hazardous to my health if I ingest them. Should I take the scientists who established this at their word, or should I check it for myself?
I don't like lemon biscuits. If the packet of Lemon Puffs is in front of me, do I take this at face value, or open the packet and check?
You take the word of others in written form, too, in a myriad of different ways. Don't you?