Ever since Descartes said, “Cogito, ergo sum (I think, therefore I am.)”, people have focused on what makes our physical world exist—essentially, how do we know that what is outside of our minds is actually out there?
A common metaphor is: “How do we know (really) that our brains are not sitting in a vat of saline and our sensations are caused by electrical impulses delivered by another being or machine?”
It doesn’t really matter. What ever I experience is true to me. Even if an electrode falsely gives the information, it is real.
Experience is the only thing that each of us understands. It is more important than any data or figures that can be given, because it has affected each of our senses.
People reading Descartes skip an important point he makes in Discourse on the Method for Conducting One’s Reason Well and for Seeking the Truth in the Sciences (1637).
Descartes believed in experience, so much so that he wrote:
That is why, as soon as age permitted me to emerge from the supervision of my teachers, I completely abandoned the study of letters. And resolving to search for no knowledge other than what could be found within myself, or else in the great book of the world, I spent the rest of my youth traveling, seeing courts and armies, mingling with people of diverse temperaments and circumstances, gathering various experiences, testing myself in the encounters that fortune offered me, and everywhere engaging in such reflection upon the things that presented themselves that I was able to derive some profit from them. For it seemed to me that I could find much more truth in the reasonings that each person makes concerning matters that are important to him, and whose outcome ought to cost him dearly later on if he has judged badly, than in those reasonings engaged in by a man of letters of study, which touch on speculations that produce no effect and are of no other consequence to him except perhaps that, the more they are removed from common sense, the more pride he will take in them, for he will have to employ that much more wit and ingenuity in attempting to render them plausible. And I have always had an especially great desire to learn to distinguish the true from the false, in order to see my way clearly in my actions, and to go forward with confidence in this life.
Obviously, since I didn’t live in 1637, I am no Descartes, and will never be one, but in my years of reading, that paragraph speaks more to me than the Declaration of Independence or the U.S. Constitution.
We will leave Descartes for a moment.
I am a rather anal person. My wife would say that I am a very anal person. Most everything I have done has been planned. Before the hunters rolled out of their sleeping bags, the crew had horses saddled, the cook had breakfast going, and the guides planned the day’s hunt.
Until another experience comes along, I will sit here on the Howard Air Force Base runway waiting for another C-130 to take me somewhere. The last one went to Puerto Rico in 1977. That was real. Even if it were administered by electrodes in a vat, it was real. Much more real than someone experiencing another's experiences.