We can't know if we're deceived because if we knew, we wouldn't be deceived. It is simply a matter of trust. No one should have blind faith (or trust). Faith results from a spiritual experience of God. One experiences the transformed life (at least in my personal experience) and their faith grows from there. I understand this can lead to all sorts of suppositions that Satan could actually be the source of this change and I understand that.
Nonetheless, one cannot exist in a total state of not believing in anything for then that itself would constitute a belief. For the years I was an atheist I felt (now) that I was deceived by the world, brainwashed by it. It was only when I experienced God that there was a difference in my life; His word became life-giving to me. I will die by that testimony than to throw all which He has brought into my life away for fear it is from Satan and not God [besides there is the Scriptural reference which indicates that Satan cannot destroy himselfelse he would be for God which is not possible, yet understand you won't hear Scriptural reference (though then I should say I won't listen to your worldly circular reasoning, but I'll humor a sincere question if it is asked respectfully and not in a deriding manner)].
I don't necessarily ignore it, I just recognize it for what it is: scientific information about the world. What the unbeliever may not understand is that believers take authority only from the Word of God. It doesn't matter what science says about the world. It may be neat stuff that can tell us lots of interesting things which should definitely make us praise the wonderful might and glory of God the Creator, yet the believer does not seek corroboration from the world to authenticate God's word. Rather, it is the other way around. If what comes from the world does not match up with what is said in the Bible, it ultimately is just not the truth, no matter what so-called "facts" from the world may tell us. The deception which resulted in the first instance of disobedience to God was not understanding His word.