There are so many ways to look at those flashes of knowing, that turn out to be accurate, and might be gathered together in the category of intuition.
They could be from the collective unconscious, from guides or angels, from archetypes to which we relate, from our chakras, from our own subconscious, from flashes of past lives, from God, or even from aliens. That just scratches the surface of things hypothesized.
Back when I was studying for ministry, I read a pile of books on mysticism - from those who studied others to the others being studied. We read Jacob Boehm, Meister Eckhart, Mechtild of Magdeburg, Hildegard of Bingen, and dozens of other mystics. We read Evelyn Underhill and Richard Bucke. So we basically studied how people had attuned themselves to the Infinite, and how we might also do so.
Richard Bucke seemed to fully believe that humans were moving into conscious union with The Divine that would be as monumental as the first self-consciousness of humans in the far distant past. He surveyed the exceptional awareness of the mystics and felt they were fortelling what was coming for us all.
At every time in history, there have been those who were in tune with the Infinite such as prophets, sages, shamen, wise ones, etc. A question I have is - does this seem to be accelerating? For a shift of all of humanity, there would have to be a critical mass, it seems to me. I see quite a few who are writing and speaking about spiritual matters, but that is still a small minority. I also see a lot of confusion, violence, fear and such in the news and in lives across the globe.
What can each of us do to attune to the Infinite? I suggest we disengage from a lot of negatives, as much as possible in this "modern" era. Spend some time reading and quietly contemplating some mystics, pick one to begin and stick with that one until you feel like you know them. Spend time just being with nature. Meditate, listen, journal. Put value on your spiritual life. Just as you would not go out without brushing your teeth and combing your hair, don't go out without bathing for a time in spiritual moments.
There is so much more to life here than you know. Seek it. Find it.