In every case, our properly basic beliefs are delivered to us through the use of our cognitive faculties. In the examples above, the beliefs that “I hold a book in my hands” and “My daughter has called my name” are delivered through the senses.
That’s just as a start. The belief that “My daughter has called my name” also depends on the cognitive faculty of memory.
That is, we assume that our memories are generally reliable, even if they are not always perfect on the details. We assume this to the degree that we do not even question it. “I was alive ten years ago” seems obviously true to us, and thus, it is properly basic.
Likewise, you believe from the past – and by no other proof – that your daughter is your daughter. You have a memory of the day she was born, of the day she came home, of her earliest days. It is this continuity of memory which causes you to believe she is your daughter.*
Let us have the quintessential demonstration of our reliance on memory: How would you prove that the Universe did not come into existence five minutes ago, with all of the appearances of being 13.8 billion years old? How would you prove that you were alive more than 5 minutes ago, if I simply say that all of those pictures, records, and memories were fabricated and planted to make you believe you were alive more than 5 minutes ago?
It is not something you can prove, unless you accept that the memory is reliable, and delivers properly basic beliefs. Then again, like doubting everything, you can try to wrestle your shadow here, and make-believe that the past is real without relying your memory. Take it up with Bertrand Russell.
*One might object that a birth certificate, or a DNA test, would also prove this. First of all, such things would only be further demonstrations of Plantinga’s point. If we know, from a DNA test, that this is your daughter – how do we know that? Can’t a DNA test be faked? Aren’t the fundamental assumptions of science just more properly basic beliefs?
The point here, of course, is that this is the ordinary way we know such things, and this way of knowing is near-universally believed. The reason is that it is properly basic.