How Do We Know What (we think) We Know?
September 21, 2025 Dr. Roger Ray
One of my favorite segments in Bill Maher’s “Real Time” shows is when he does his, “I don’t know it for a fact, I just know it is true” routine. Maher will say something like, “I don’t know it for a fact that Elon Musk is going to grow a moustache just to own the libs; I just know it is true.”
Or, “I don’t know for a fact that RFK, Jr. did something weird with the body of the dog that Kristi Noem shot; I just know it’s true.”
Sadly, Bill Maher’s schtick is making fun of a real phenomenon which is just too common in our public discourse. People find it exciting to speculate aloud that those vapor trails we see behind high flying jets are really mind control drugs being dropped on the population or that the covid vaccine contains a tiny GPS that will allow Bill Gates to track you to the local drug den or strip club. People will say it, then repeat it with conviction, and then it is picked up by talk radio hosts, and finally it is repeated by Donald Trump on Truth Social and the next thing you know our president is telling us that it true because a lot of people are saying it.
It is embarrassing that so many adults are willing to believe the most preposterous things, so much so, that a lot of us have become so cynical that we tend to not believe anything at all . . . we can reasonably assume that politicians, political parties, the news media, university professors, and the people you meet on dating sites are all liars with some barely concealed ulterior motive to trick you or manipulate you. I am much more cynical than I once was, less trusting, more suspicious . . . 20 years ago I almost always voted for whatever amendment was on the ballot, assuming that my state legislators surely know what they are doing and if they wrote up the amendment, we must need it. Experience has taught me to go to the other extreme, almost always voting no unless I have had the time to research the proposal and find that it is a good amendment. In the past few elections, I have probably voted against bridges and paved roads just out of a reflexive mistrust of state government.
But here is the good news, fairly reliable knowledge is not impossible. We can never be absolutely certain of much, but we can reasonably attain reliable knowledge about most of the things that affect us, though we’ll probably always have some things that we believe that we can’t prove, but we just know that they are true. For example, I have no idea whether Jeffy Epstein committed suicide in prison, I just know that the obvious coverup and official attempts at distraction make me think that he really did have incriminating evidence on a lot of powerful people, especially Donald Trump, such that I find it more plausible to believe that he was murdered rather than believe that he committed suicide, during a brief and unexplained interruption in the recording of security cameras in a prison. I don’t know for a fact that he was murdered, I just know that it is true.
A man with a long history of pedophilia and con jobs is certainly a malignant narcissist and they are unlikely to ever commit suicide, especially when they have the goods on presidents and royalty and billionaires. Still, even though a malignant narcissist is unlikely to take their own life, it isn’t hard to imagine a malignant narcissist killing someone to hide a dirty secret. You do the math. And by malignant narcissist, I mean Donald Trump. But, I’ve moved on.
There is actually a dimension of philosophy, born in the writings of Aristotle, that is devoted to how we know what we know. It is called “epistemology,” which may sound a bit daunting but, honestly, at least on the surface, it isn’t that tough.
You may think that you don’t know what the term “epistemology” means but even the uninitiated are familiar with Rene Descartes’ most famous maxim: “I think, therefore, I am,” the famous “cogito ergo sum.” In Descartes’ Meditations he sets out to doubt everything, all of the way down to his own existence. How, after all, do any of us know that we actually exist. Many people seem to think that when they watched the Matrix that it was more of a documentary than a science fiction film.
But even if we are captured in the Matrix, with a fake world being projected into our minds, still, the fact that we are aware of our own thinking is singular proof that, at least in some form, we must exist.
In epistemology, there are two kinds of knowing, knowing like Descartes’ Cogito is called a posterioriknowledge because it is derived from experience. All of science is predicated on this kind of knowing. The scientific method seeks to articulate facts based on observation, repetition, and analysis. The other kind of knowing is called a priori or knowledge we have before or even without experience. A new born baby knows to root for a nipple without ever having taken the class in breast feeding.
Which is rather less impressive when you consider the construction and engineering skill of the southern masked weaver of Africa, which constructs its intricate nests out of wide strips of grass, reeds, and/or palm blades. Birds just know how to make the nest that is unique to its species, except for the dull thug birds who take other nests or just lay their eggs in another female’s nest. Still, they are born with a survival instinct which is noteworthy even if it isn’t laudable.
There are things we at least think we know without experience. Things that are either somehow revealed to us or revealed to someone else whom we are inclined to believe. All religions tend to fall under the category of, “I don’t know it for a fact, I just know that it is true.”
Religions have traditionally valued belief without evidence while science places little or no value on belief without evidence.
Personally, I favor an evidence based faith, something I wrote about in longer form in my 2014 book, Progressive Faith and Practice.
People often assure themselves and others that God has spoken to them or revealed something to them miraculously. Science dismisses such a priori evidence because it cannot be repeated, observed, or analyzed. It doesn’t mean that it isn’t true, it just means that you cannot know if it is true or not. Many people believe in ghosts because, they say, they saw one but their personal experience doesn’t pass the test of critical thinking because the experience cannot be repeated, observed, or tested. If your experience cannot be repeated, observed, and tested then, it is your belief to keep if you want but it shouldn’t be a belief to anyone else.
All of the Quran are sayings that Muhamad claimed were revealed to him by the angel Gabriel but no one else saw Gabriel or heard his voice. Hence all of Islam is based on the a priori conviction of Muhamad and if you are not disposed to give Muhamad that kind of credibility, the whole thing falls apart. This can be said of other world religions as well. I have received many a blank stare from someone who quoted Buddha to me when I tell them that no one wrote down any of the teachings of Buddha until Buddha had been dead for more than 400 years. That stretches credibility a good deal farther than I am willing to go. There is no historical evidence for the teachings of Buddha, there is just Buddhist tradition. It may be very helpful, very insightful, very valuable . . . but it is highly unlikely that it came from Buddha.
That is not to say that there is not a lot of wonderful things in the Buddhist dharma, the Muslim Quran, or the Christian Bible, it is just that none of it is supported by anything we can rationally call evidence. As existentialists often do, we just sometimes say, “It pleases me to think so,” and we leave it at that. A priori knowledge isn’t bad, just look at the nest of the southern masked weaver. I don’t know how the knowledge of how to make that nest is passed along, but, clearly, it is passed along.
We know from physics that everything in the world, all matter of all sorts, was created by the energy of exploding stars. Everything from earthworms to air planes is made up of the same 12 particles of matter which are held together by the same 4 forces of nature. For many years I frequently pointed out that the hundred pound Ficus tree in my living room was made of exactly the same stuff as my 100 pound daughter and yet, existentially, I knew that the two were not the same, certainly not the same value to me. I liked my Ficus tree which I kept for nearly 40 years, but I love my daughter more than I love anything, to include my own life.
I don’t know that I love my daughter based on a medical test or something I can see in a microscope. I know it because I feel it, and it is as real to me as the light and heat from the sun, but I cannot prove it to you in any scientific way. Both kinds of knowledge have value and have a place in our thoughts, but critical thinking demands evidence about most things in life.
What has become dangerous in our time is how “it pleases me to think so” has come to take the place of real evidence and analysis. Has, for example, Donald Trump really stopped 10 wars in the past few months? Could he find the countries in question on a map? Could he even name them? Does he think that he has stopped the wars in Ukraine and the Gaza Strip because he has told the parties to stop fighting?
Are cities with black Democrat mayors really more dangerous than cities with white Republican mayors, even if these Republican run cities have murder and crime rates that are 4 times higher than the Democrat managed cities where he wants to send in the Army? It pleases Trump to think so, and it pleases the racists in his base, but that doesn’t make it so. Facts are, after all, stubborn things.
Most politicians lie, at least some of the time, but what is dangerous in our time is the unprecedented way in which Trump tries to bend reality to his whims. He literally tried to convince people that they were in danger from a hurricane because he drew, with a sharpie, and a weather map to extend the threat posed by the hurricane. In his second administration, he has just cut funding to the actual weather scientists who help to forecast dangerous weather. Trump fired Erika McEntarfer, the commissioner of the Bureau of Labor Statistics. He claimed that the country's jobs reports "are being produced by Biden appointee" and were therefore suspect. She gave him a factual report with numbers that made Trump look bad so he fired the researcher who brought him bad news.
Good government depends on good factual information but everything Trump says is on par with your delusional aunt who talks to ghosts. The Trump administration’s plan for implementing his fascist take down of American democracy has been to “flood the field” with so many conspiracy theories, lies, propaganda, and crazy executive orders that the media can’t keep up and the voting public will just get so disgusted that they stop paying attention. This “flood the field” technique is working for them.
Those of us who try to respond to the constant drum beat of idiotic claims, misinformation, and crimes are labeled as having “Trump Derangement Syndrome” suggesting that the problem is that we hate Trump so much that we are against everything that he says and does. This is just another way of evading the central fact that our president is an uneducated, low IQ, fascist who is the greatest threat to democracy since Hitler. We’re not deranged; we’re devoted to reality even though this reality is increasingly nightmarish.
Folks, the moon landing happened. The earth is not flat. There are no mind control drugs in the vapor trails left behind jets. Tariffs cause inflation, and can cause a major economic meltdown. The Trump “big beautiful bill” cut millions of people off of access to healthcare in order to give huge tax breaks to the richest 1% who do not need a tax break. Russia started the war with Ukraine and giving Russia Ukrainian land will only guarantee that Russia will invade other neighbors to take more territory. One need only watch the sycophantic exercise of every cabinet meeting to realize that Trump wants to be a dictator and he is appointing people to posts who are so stupid and loyal that he has no one to stop him from becoming a dictator.
And these things, my friends, I will tell you that I do know for a fact and I hope that you also realize that they are true and that you will act on them.
