How do you know that the author of these words has a mind?
Step 1 — Is it a reasonable inductive inference to conclude that the author of those words has a mind?
“Mind” is a concept I use to refer to the collection of things that I do “within myself”. It is my concept for the collection of mental processes that is my thinking, reasoning, conceptualizing, feeling, sensing, desiring. It is my concept for what it is that is conscious when “I” am conscious.
Other people are very much like me in many respects. In particular, I have acquired convincing evidence to justify the inductive inference that other people have brains. Every person who was alive, and has been examined after death, has had a brain. Brain surgery is an acknowledged field of medical expertise. And medical imaging technologies can image a soft-tissue organ beneath the skull of living subjects. It is an inference that has so far proved successful at predicting the results of autopsies and other such medical stories. So I feel confident in my inductive inference that every person has a brain.
I have, over my years, acquired convincing evidence to justify the inductive inference that all aspects of my “mind” are actions of my physical brain. For example, it is obvious to me that my point-of-view is behind my glasses, between my ears, below my scalp, and above my neck. There is no evidence I am aware of that would suggest that my “mind” might not be a part of my physical presence. For example, I have never been able to make my point-of-view move from a position behind my glasses, above my neck, etc.
This highly subjective evidence is supported by all of the scientific information that I am aware of. According to this scientific information, the locus of my thinking, reasoning, conceptualizing, feeling, sensing, desiring is my physical brain. And there is no scientific evidence I am aware of that would suggest that my mind or my consciousness is elsewhere. The scientific evidence I must take with a grain of salt, however. Since it is based on the premise that what other people actually do with their brains is thinking, reasoning, conceptualizing, etc. Which is the conclusion I am trying to justify. So to avoid arguing in circles, I must take the scientific evidence not as demonstrative of, but merely as consistent with, the hypothesis that the brain is the locus of my mind.
Therefore I can justify the inductive inference that my “mind” is identical to my physical brain. The processes that constitute my thinking, reasoning, conceptualizing, feeling, sensing, and desiring are physical processes taking place within my physical brain. And since every person has a brain, I can reason that therefore every person might possibly also have a mind.
I reason, conceptualize, have thoughts, feelings, and desires that I make use of language to enable, assist, describe and express. My use of language is as a tool of my mind.
I observe that other people employ language in ways that appear superficially similar to my use of language. Specifically, I observe that other people employ language to describe and express what would be thoughts, reasoning, conceptualizing, feelings, and desires — if I were the one making the statements. Therefore, I can conclude either (a) that other people are making use of language as a tool of their mind; or (b) their use of language, however else generated, closely mimics my use of language as a tool of my mind.
I observe that attributing the actions of “mind” to other people is, more often than not, an effective and efficient way of understanding and predicting their behaviour. I have acquired convincing evidence over my years that attributing feelings, and desires to other people is a good way to explain their behaviour. More specifically, their observable reactions to what I say and do closely mimic the reactions I would display, given the thoughts, feelings, and desires I would have, if I were in their place. My predictive capacity in this field is not total. I experience a high error rate. So it might very well be the case that other people generate their language and other behaviour in some fashion not involving a mind. However, I judge that it is more economical for me to make use of the “mind” hypothesis and deal with the error rate, than it would be to attempt to develop a more predictably accurate “black-box” theory.
Therefore I judge that I can justify an inductive inference that the use of language in ways similar to the way I would use it, is indicative of the presence of a mind similar to mine. In other words it is a reasonable inductive inference to conclude that the author of those words has a mind. This is not a strongly justified inductive inference, as it does not work all the time. It is, however, the best currently available basis upon which to proceed. And I have no evidence in hand that might suggest that circumstances are otherwise.
Step 2 — Given that “knowledge” is “a justified true belief”, do I have sufficient justification to warrant a claim to know that the author of those words has a mind?
Obviously, given the material of Part 1 above, I have a belief that the author of those words has a mind. Also obviously, there is a fact of the matter whether my belief is true or not. However, just as obviously, I cannot determine with any certainty whether my belief is true or not. I cannot climb into the alleged “mind” if any other person to see for myself. All I have is the evidence of their observable behaviour, and the inferences I can draw there from. But I do have a significant amount of very persuasive evidence — even though it is not overwhelming. And more importantly, I am aware of no “defeater” evidence. So, while it is certainly possible that my inductive inferences may in fact be wrong, it is unlikely.
And ultimately, whether we have “knowledge” or a mere “Silly wild assed guess” is a subjective evaluation. Along that continuous scale between “wild guess”, and “certain knowledge”, will be a line drawn. To one side, we maintain that what we think is merely an unjustified opinion or belief, and to the other side we maintain that what we believe rates the label of “knowledge”. Close to the line, we will be uncertain which is which. Further from the line, we will have a great deal of confidence in which is which. But the choice of where a particular belief falls along that scale relative to the location of that dividing line is largely a subjective evaluation.
It is my subjective judgement that I have sufficient evidentiary justification to warrant calling my belief knowledge. Therefore, I claim that I do indeed know that the author of those words has a mind.