Reason Not The Only Source of Knowledge
#1622·Dennis Hackethal revised 4 months agoIs irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if irrationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, mysticism, and more examples of irrationality. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
Hi Dennis. You say there can't be true irrational ideas. You also say (#1625) that calling an idea irrational can be short for calling its holder irrational. Consider an irrational person believing some true idea. He is told criticisms he can't address. If he still considers the idea true without addressing those criticisms, if he evades the issue, then he's still being irrational even though the idea is true.
#1637·Dennis Hackethal, 4 months agoIs this kid being irrational?
Perhaps not. However, I find your example implausible. Let’s look at it more closely. You originally wrote that a belief in god could be rational if two conditions are both met:
- “[The] belief stems from a sincere effort to explain the world and …”
- “… the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.”
As for 1, a sincere effort to explain the world implies a critical attitude, honesty, conscientiousness/thoroughness, which means subjecting candidate ideas to lots of criticism, following up on counter-criticisms (as opposed to running off and doing something else), etc. A child might prioritize playing in the dirt today, but at some point he will ask questions. A sincere effort to explain anything means he’d rather say ‘I don’t know’ than believe something as silly as god.
God as a concept is arbitrary on its face. It cannot survive even very basic criticism. So it cannot possibly stem from a sincere effort to explain the world.
As for 2, kids ask tons of questions and criticize ideas. They’re naturally curious and conscientious in this way. The problem is that parents beat the god idea into their kids (figuratively if not literally) so that the kids don’t question it. So then those kids are not willing to jettison the idea anymore. Which is why the idea sticks around despite not being a sincere effort to explain the world.
Yeah fair. I'll admit, my example is rather contrived. My hope was to show that one could in principle maintain a belief in god in a rational fashion, at least for a time. However, just because it is theoretically possible doesn't mean that it is at all likely. I agree that this isn't what is usually going with believers.
#1629·Amaro Koberle revised 4 months agoI agree that a belief in god is mystical, but I disagree that the fact that god doesn't exist must be blatant and that believing in god must necessarily involve some dishonest refusal to look into the matter. Or, perhaps to be more precise: The refusal to look into the matter could be a result of genuine disinterest in the light of more pressing problems, rather than some irrational fear response to changing one's mind on the topic.
Perhaps consider a child growing up on a medieval farm in Europe. His entire social context is certain of the existence of god, the kid would never encounter any criticism of it without creating it himself. Water is wet, fire is hot and the universe was created by sky daddy. He didn't ask for this last "fact", it's just what mom and dad told him. He's young, he doesn't really care, he's much more interested in a thousand other things, so he heard of god once, thought to himself "alright, whatever" and went straight back to wondering about whether the dirt in the yard could possibly make for a tasty meal. Perhaps if this kid was to encounter some argument for why the universe cannot have been created by an omnipotent being, the child would just say "ah alright, now that you say it that way, it does sound a bit silly..." and upon examining the matter critically for a mere second the kid would ditch his belief in god without further ado. The reason why he hasn't done so is because he was occupied with things other than the big questions of the origins of the cosmos, the meaning of life and what not. Is this kid being irrational?
Is this kid being irrational?
Perhaps not. However, I find your example implausible. Let’s look at it more closely. You originally wrote that a belief in god could be rational if two conditions are both met:
- “[The] belief stems from a sincere effort to explain the world and …”
- “… the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.”
As for 1, a sincere effort to explain the world implies a critical attitude, honesty, conscientiousness/thoroughness, which means subjecting candidate ideas to lots of criticism, following up on counter-criticisms (as opposed to running off and doing something else), etc. A child might prioritize playing in the dirt today, but at some point he will ask questions. A sincere effort to explain anything means he’d rather say ‘I don’t know’ than believe something as silly as god.
God as a concept is arbitrary on its face. It cannot survive even very basic criticism. So it cannot possibly stem from a sincere effort to explain the world.
As for 2, kids ask tons of questions and criticize ideas. They’re naturally curious and conscientious in this way. The problem is that parents beat the god idea into their kids (figuratively if not literally) so that the kids don’t question it. So then those kids are not willing to jettison the idea anymore. Which is why the idea sticks around despite not being a sincere effort to explain the world.
#1627·Amaro Koberle, 4 months agoI agree that a belief in god is mystical, but I disagree that the fact that god doesn't exist must be blatant and that believing in god must necessarily involve some dishonest refusal to look into the matter. Or, perhaps to be more precise: The refusal to look into the matter could be a result of genuine disinterest in the light of more pressing problems, rather than some irrational fear response to changing one's mind on the topic.
Perhaps consider a child growing up on a medieval farm in Europe. His entire social context is certain of the existence of god, the kid would never encounter any criticism of it without creating it himself. Water is wet, fire is hot and the universe was created by sky daddy. He didn't ask for this last "fact", it's just what mom and dad told him. He's young, he doesn't really care, he's much more interested in a thousand other things, so he heard of god once, thought to himself "alright, whatever" and went straight back to wondering about whether the dirt in the yard could possibly make for a tasty meal. Perhaps if this kid was to encounter some argument for why the universe cannot have been created by an omnipotent being, the child would just say "ah alright, now that you say it that way, it does sound a bit silly..." and upon examining the matter critically for a mere second the kid would ditch his belief in god without further ado. The reason why he hasn't done so is because he was occupied with things other than the big questions of the origins of the cosmos, the meaning of life and what not. Is this kids belief in god irrational?
Superseded by #1629.
#1631·Zelalem MekonnenOP revised 4 months agoAyn Rand claims that "The virtue of Rationality means the recognition and acceptance of reason as one's only source of knowledge," This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.
That quote is better but still not quite right. You’d want to end it not in a dangling comma, but in an ellipsis to indicate that you’re cutting the sentence short. Try changing it to:
"The virtue of Rationality means the recognition and acceptance of reason as one's only source of knowledge […]." This is wrong etc.
Then, in the section “Do the comments still apply?”, be sure to deselect the criticisms that your edit addresses.
#1632·Zelalem MekonnenOP, 4 months agoI didn't copy/paste, no. I try not to whenever possible. It helps with paying attention to the detail.
In other situations, I would agree. For example, back when I was first learning how to code, I made it a point to type code from tutorials manually to retain it better.
But with quotes it’s different because retaining the literal letter matters. Typing it manually is too error prone and there’s no compiler (except Quote Checker) to catch errors.
The source of knowledge is myths. Reason criticizes them and we get myths that are testable (if knowledge about the physical world), hard to vary and make some assertion about reality. Popper highlighted the myth and testable nature of scientific knowledge, and Deutsch highlights hard to vary and explanation/assertion nature of knowledge.
#1619·Dennis Hackethal, 4 months agoThat’s technically a misquote of Rand. https://www.quote-checker.com/diffs/checking-ayn-rand-quote-re-rationality
How did that happen? Did you not copy/paste?
I didn't copy/paste, no. I try not to whenever possible. It helps with paying attention to the detail.
Ayn Rand claims that "the virtue of rationality means the recognition and acceptance of reason as one's only source of knowledge." This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.
Ayn Rand claims that "The virtue of Rationality means the recognition and acceptance of reason as one's only source of knowledge," This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.
Changed the final question to asking about the irrationality of the kid rather than the irrationality of the kid's belief in god, in light of Dennis saying that irrationality is a property of minds rather than ideas (further down).
I agree that a belief in god is mystical, but I disagree that the fact that god doesn't exist must be blatant and that believing in god must necessarily involve some dishonest refusal to look into the matter. Or, perhaps to be more precise: The refusal to look into the matter could be a result of genuine disinterest in the light of more pressing problems, rather than some irrational fear response to changing one's mind on the topic.
Perhaps consider a child growing up on a medieval farm in Europe. His entire social context is certain of the existence of god, the kid would never encounter any criticism of it without creating it himself. Water is wet, fire is hot and the universe was created by sky daddy. He didn't ask for this last "fact", it's just what mom and dad told him. He's young, he doesn't really care, he's much more interested in a thousand other things, so he heard of god once, thought to himself "alright, whatever" and went straight back to wondering about whether the dirt in the yard could possibly make for a tasty meal. Perhaps if this kid was to encounter some argument for why the universe cannot have been created by an omnipotent being, the child would just say "ah alright, now that you say it that way, it does sound a bit silly..." and upon examining the matter critically for a mere second the kid would ditch his belief in god without further ado. The reason why he hasn't done so is because he was occupied with things other than the big questions of the origins of the cosmos, the meaning of life and what not. Is this kids belief in god irrational?
I agree that a belief in god is mystical, but I disagree that the fact that god doesn't exist must be blatant and that believing in god must necessarily involve some dishonest refusal to look into the matter. Or, perhaps to be more precise: The refusal to look into the matter could be a result of genuine disinterest in the light of more pressing problems, rather than some irrational fear response to changing one's mind on the topic.
Perhaps consider a child growing up on a medieval farm in Europe. His entire social context is certain of the existence of god, the kid would never encounter any criticism of it without creating it himself. Water is wet, fire is hot and the universe was created by sky daddy. He didn't ask for this last "fact", it's just what mom and dad told him. He's young, he doesn't really care, he's much more interested in a thousand other things, so he heard of god once, thought to himself "alright, whatever" and went straight back to wondering about whether the dirt in the yard could possibly make for a tasty meal. Perhaps if this kid was to encounter some argument for why the universe cannot have been created by an omnipotent being, the child would just say "ah alright, now that you say it that way, it does sound a bit silly..." and upon examining the matter critically for a mere second the kid would ditch his belief in god without further ado. The reason why he hasn't done so is because he was occupied with things other than the big questions of the origins of the cosmos, the meaning of life and what not. Is this kid being irrational?
#1625·Dennis Hackethal, 4 months agoSo the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
I agree, yeah. I think (ir)rationality has to do with an attitude toward ideas and truth seeking. It’s a property of minds, not ideas. (Though as a shorthand, calling a belief in god irrational is fine, I think, as long as we know that we’re calling the holder of that idea irrational, not literally the idea itself.)
The idea that irrationality is a property of minds rather than individual ideas is interesting, I hadn't considered it.
#1623·Dennis Hackethal, 4 months agoIf I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
A belief in god is a form of mysticism. Rand writes that rationality “means the rejection of any form of mysticism […].” So a belief in god is not just false, it’s irrational. It’s also implausible that someone could hold on to as blatantly false an idea as the existence of god without some refusal to look into the matter critically.
I agree that a belief in god is mystical, but I disagree that the fact that god doesn't exist must be blatant and that believing in god must necessarily involve some dishonest refusal to look into the matter. Or, perhaps to be more precise: The refusal to look into the matter could be a result of genuine disinterest in the light of more pressing problems, rather than some irrational fear response to changing one's mind on the topic.
Perhaps consider a child growing up on a medieval farm in Europe. His entire social context is certain of the existence of god, the kid would never encounter any criticism of it without creating it himself. Water is wet, fire is hot and the universe was created by sky daddy. He didn't ask for this last "fact", it's just what mom and dad told him. He's young, he doesn't really care, he's much more interested in a thousand other things, so he heard of god once, thought to himself "alright, whatever" and went straight back to wondering about whether the dirt in the yard could possibly make for a tasty meal. Perhaps if this kid was to encounter some argument for why the universe cannot have been created by an omnipotent being, the child would just say "ah alright, now that you say it that way, it does sound a bit silly..." and upon examining the matter critically for a mere second the kid would ditch his belief in god without further ado. The reason why he hasn't done so is because he was occupied with things other than the big questions of the origins of the cosmos, the meaning of life and what not. Is this kids belief in god irrational?
#1617·Amaro Koberle, 4 months agoCopying from another chat where Dennis and I were discussing Rand's conception of irrationality:
Amaro:
What's an irrational idea to you? I understand anti-rational (immunized against criticism) and rational (subject to criticism). Is irrational just "false" or is there something else to it? Are there true but irrational ideas? I think rational but false ideas must exist, no?Could the same mistaken idea (belief in god, say) be either rational, anti-rational or irrational depending on how exactly it is instantiated in the mind? Or must any particular idea always fall within one and only one of those categories?
Dennis:
Great questions. You’ll find answers to most if not all of them here: https://aynrandlexicon.com/lexicon/rationality.htmlI disagree with some of it, but if you basically just ignore the small bits about perception and the senses, the rest is still very good
Amaro:
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
To Rand, it seems that irrationality is tied to a lack of commitment to truth, almost like an internal insincerity.If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
So the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
So the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
I agree, yeah. I think (ir)rationality has to do with an attitude toward ideas and truth seeking. It’s a property of minds, not ideas. (Though as a shorthand, calling a belief in god irrational is fine, I think, as long as we know that we’re calling the holder of that idea irrational, not literally the idea itself.)
#1621·Dennis Hackethal revised 4 months agoIs irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if rationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, the rejection of mysticism, and more. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
You asked if rationality was just false or if there was something else to it.
Irrationality, not rationality.
#1617·Amaro Koberle, 4 months agoCopying from another chat where Dennis and I were discussing Rand's conception of irrationality:
Amaro:
What's an irrational idea to you? I understand anti-rational (immunized against criticism) and rational (subject to criticism). Is irrational just "false" or is there something else to it? Are there true but irrational ideas? I think rational but false ideas must exist, no?Could the same mistaken idea (belief in god, say) be either rational, anti-rational or irrational depending on how exactly it is instantiated in the mind? Or must any particular idea always fall within one and only one of those categories?
Dennis:
Great questions. You’ll find answers to most if not all of them here: https://aynrandlexicon.com/lexicon/rationality.htmlI disagree with some of it, but if you basically just ignore the small bits about perception and the senses, the rest is still very good
Amaro:
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
To Rand, it seems that irrationality is tied to a lack of commitment to truth, almost like an internal insincerity.If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
So the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
A belief in god is a form of mysticism. Rand writes that rationality “means the rejection of any form of mysticism […].” So a belief in god is not just false, it’s irrational. It’s also implausible that someone could hold on to as blatantly false an idea as the existence of god without some refusal to look into the matter critically.
Is irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if rationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, the rejection of mysticism, and more. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
Is irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if irrationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, mysticism, and more examples of irrationality. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
Is irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if rationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, the rejection of mysticism, and more. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
Is irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if rationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, the rejection of mysticism, and more. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
#1617·Amaro Koberle, 4 months agoCopying from another chat where Dennis and I were discussing Rand's conception of irrationality:
Amaro:
What's an irrational idea to you? I understand anti-rational (immunized against criticism) and rational (subject to criticism). Is irrational just "false" or is there something else to it? Are there true but irrational ideas? I think rational but false ideas must exist, no?Could the same mistaken idea (belief in god, say) be either rational, anti-rational or irrational depending on how exactly it is instantiated in the mind? Or must any particular idea always fall within one and only one of those categories?
Dennis:
Great questions. You’ll find answers to most if not all of them here: https://aynrandlexicon.com/lexicon/rationality.htmlI disagree with some of it, but if you basically just ignore the small bits about perception and the senses, the rest is still very good
Amaro:
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
To Rand, it seems that irrationality is tied to a lack of commitment to truth, almost like an internal insincerity.If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
So the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
Is irrational just "false" or is there something else to it?
There’s more to it.
Are there true but irrational ideas?
I don’t think so, no.
I think rational but false ideas must exist, no?
Yes. Mere falsehood does not imply irrationality.
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
You asked if rationality was just false or if there was something else to it. Note that the word ‘false’ does not occur on the linked page. Instead, she mentions the destruction of life, dishonesty, lack of integrity, context dropping, the rejection of mysticism, and more. These are attitudes toward truth seeking and their effects.
You asked whether rational but false ideas must exist. That is what Rand means by “not blindness, but the refusal to see, not ignorance, but the refusal to know.” Blindness = being wrong on some issue, refusal to see = refusing to seek or recognize the truth on some issue. To her, blindness and the refusal to see are not the same thing, which answers your question.
If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
#1616·Zelalem MekonnenOP, 4 months agoAyn Rand claims that "the virtue of rationality means the recognition and acceptance of reason as one's only source of knowledge." This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.
That’s technically a misquote of Rand. https://www.quote-checker.com/diffs/checking-ayn-rand-quote-re-rationality
How did that happen? Did you not copy/paste?
#1616·Zelalem MekonnenOP, 4 months agoAyn Rand claims that "the virtue of rationality means the recognition and acceptance of reason as one's only source of knowledge." This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.
What do you think is the source of knowledge if not reason?
Copying from another chat where Dennis and I were discussing Rand's conception of irrationality:
Amaro:
What's an irrational idea to you? I understand anti-rational (immunized against criticism) and rational (subject to criticism). Is irrational just "false" or is there something else to it? Are there true but irrational ideas? I think rational but false ideas must exist, no?
Could the same mistaken idea (belief in god, say) be either rational, anti-rational or irrational depending on how exactly it is instantiated in the mind? Or must any particular idea always fall within one and only one of those categories?
Dennis:
Great questions. You’ll find answers to most if not all of them here: https://aynrandlexicon.com/lexicon/rationality.html
I disagree with some of it, but if you basically just ignore the small bits about perception and the senses, the rest is still very good
Amaro:
Okay I read it. Not sure I'm clear on my questions after doing so to be honest.
To Rand, it seems that irrationality is tied to a lack of commitment to truth, almost like an internal insincerity.
If I get her right, one could in principle hold a rational belief which is false —a belief in god, say— so long as this belief stems from a sincere effort to explain the world and so long as the believer is ready to jettison his belief if he were to think of some reason why it cannot be true.
So the same mistaken idea could be rational in one person's mind and irrational in another person's mind depending on whether that person is committed to the truth and ready to ditch the idea should they find some reason to do so.
Did I get this right?
Ayn Rand claims that "the virtue of rationality means the recognition and acceptance of reason as one's only source of knowledge." This is wrong, mainly because reason can only be used as a method of choosing between knowledge/ideas, not as a source of knowledge.