People usually talk as if it was some absolute truth what they are saying. What philosophy has taught me is that we cannot be sure of anything. For everything there exists some counterargument. If a person tells me that 2+2=4 without some other information to justify it (by saying for example that it is true only if you accept some axioms and rules of inference as true), it doesn't seem obviously true to me at all. Another example could be the following: I'm standing on a street, next to me stands John and right in front of us stands a huge house. John tells me "in front of you stands a huge house," as it was some absolute fact that cannot be doubt by some "brain in a vat" argument. Yes, it makes sense to me that he doesn't say "In front of you stands a huge house if you accept that what you see is real etc etc."

I wonder how do we call this tendency to call things to be facts without further justification, even though we might sometimes know that the thing we are saying is based on some implicit assumptions of ours? Is there some name in philosophy for common assumptions in the community (in a sense as if it would be some "axioms" which the community in which a person lives implicitly assumed and don't justify, because everyone know the assumed "axioms" in this community)? Are there some keywords for this topic you would recommend me to google and read about?

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    Dogmatists..... Apr 17, 2020 at 9:18
  • This "tendency" is called common sense: doubting apparent facts is idle without a positive reason to do so, even as some will turn out to be false. The implicit assumptions Peirce called "indubitable beliefs". Wittgenstein called (some of) them "hinge propositions":"The questions that we raise and our doubts depend upon the fact that some propositions are exempt from doubt, are as it were like hinges on which those turn... If I want the door to turn, the hinges must stay put." True/false does not apply to these.
    – Conifold
    Apr 17, 2020 at 10:05
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    I don't know what it's called, this tendency we have to be unaware of how little we actually know. but it may be the greatest problem of philosophy and the most significant obstacle. You can see it at work all the time. It's the opposite Cartesian doubt. . . ,
    – user20253
    Apr 17, 2020 at 11:52
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    Pragmatism. Questioning any other domain as deeply as philosophy simply is not practical. And philosophy itself is a degenerate case of a language game. Check out the later Wittgenstein... Your case of the community with a common agreement to not question a given set of facts is the general case for all communities with languages. You don't need a word for something that is true of all cases to which it might be applied. It becomes a corrollary to the definition. Apr 18, 2020 at 0:15
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    I think you have a wrong idea about it. There is no name because there is no "set of community assumptions". There are no "assumptions", as in something that is or can be spelled out that others can recognize and take into account. There is not even a neutral language in which to spell them out. Others, like you, have to master the community's practice itself to "get" it. And that is far more like training than reading. It requires acquiring practical skills, not applying non-existent universal rules to community-specific premises. The rules and the skills are themselves community specific.
    – Conifold
    Apr 18, 2020 at 1:10

2 Answers 2


You may like to look up conventionalism first and proceed further as you discover more concepts.

However, I'd like to add here that even as you seek a term to name a certain attitudes in people's spoken words, your examples, especially the first one, 2+2=4, could have been more involved, like for ex failure+anxiety=suicide. You can't accept the truth of this assertion without hearing some additional explanations. 2+2=4 is quite clearly a universal truth, since all of us have learnt this by rote since our kindergarten days. Conventionalism obviates a need for explanations in much of our daily communications.

It is in fact a trait with people to talk about certain issues as if it is self evident universally even when a deeper lookup raises some doubts and even down right contradictions. It would go unchecked within communities who have been told that the implied truth is a fact. Much of the religious superstitions fall in this category.

After reading Ayn Rand, and several times over, I revised much of the common expressions I had taken for granted as true. In one sense, I was like that character in Atlas Shrugged, the 'wet nurse' Deputy Director of Distribution appointed at Reardon Steel. He was a qualified engineer who accepted unchecked truths like "there are no absolutes". His metamorphosis as a man of wisdom is one of many ways that Rand taught me & rectified my own wisdom.

I am in a way stating in conclusion that you may like to review your own philosophic learning. You've said at the outset "philosophy has taught me is that we cannot be sure of anything". If that were to be true, how are we at all going to exchange ideas, understand each other, and grow individually? Please think it over in right earnest. Best wishes.

  • Thanks for your comment. Just to react on your "If that were to be true, how are we at all going to exchange ideas, understand each other, and grow individually?", I would like to say that you are right in that, but also I would add that we should always doubt things we think we know "for sure". Rethinking some knowledge often leads to new insights in a lot of domains and usually better conceptual understanding of the world.
    – TKN
    Apr 17, 2020 at 20:13
  • For example, when I was younger I have never questioned science, meaning scientific method. Now after I have read some philosophy, I see a lot of implicit premises in scientific method which can be questioned.
    – TKN
    Apr 17, 2020 at 20:18
  • A better way to put what you want to convey is, we should be open to new evidences that may turn our "for sure" things upside down. This is anyway s given once you are scientific (logic, evidences, reality). Pl clarify which 'philosophy' led you to question scientific methods & which are those implicit premises you want to question. I may also like to caution in your doubting things always, as you may end up getting a knitted brow permanently, like a Doubting Thomas 🤨🙂. Apr 19, 2020 at 5:22

It's a normative bias: the tendency to accept the conventional as true. I see a red ball, and I am accustomed (from habit and experience) to the idea that the red balls I see are tangible artifacts in the world, not holograms, hallucinations, or hairless hedgehogs. So I skip over all the intermediary logical steps and assert that the red ball is real. If I have a reason to question it, I can, but there is a vast difference between questioning an instance ("is that particular red ball real?") and questioning a norm ("are any of the red balls I ever see real?"). Questioning norms creates existential angst and other distressing 'dark nights of the soul', so people resist it as they can.

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