February 28, 2012

The elusive taste of pineapple

On the opening pages of Treatise of Human Nature, David Hume famously talks about a

plain and convincing phaenomenon; which is, that, where-ever by any accident the faculties, which give rise to any impressions, are obstructed in their operations, as when one is born blind or deaf; not only the impressions are lost, but also their correspondent ideas; so that there never appear in the mind the least traces of either of them. Nor is this only true, where the organs of sensation are entirely destroyed, but likewise where they have never been put in action to produce a particular impression. We cannot form to ourselves a just idea of the taste of a pine apple, without having actually tasted it.

This sounds natural enough: the congenitally blind cannot understand colour language, the congenitally deaf can have no idea of the sound of a trumpet or clarinet, and someone who has never tasted pineapple can’t form an idea of what it tastes like. Hume is here arguing for his central doctrine that all our ideas (anything we can talk or think about) have to originate in sense-impressions: we learn what red is by having a visual impression of red, what the taste of pineapple is by having the sensation of tasting pineapple, etc. (Hume would probably have conceded that this need not be literally true: someone might be able to produce a pineapple-tasting compound in the lab and teach us the taste of pineapple by means of it.)

Is Hume right here? What type of claim is he making?

There appear to be two sides to the claim, one apparently psychological, the other concerning understanding. Hume seems to be saying that under certain conditions (in the absence of having tasted pineapple) certain mental contents (or qualia as philosophers would nowadays call them) will not occur. In consequence of this, the person “cannot form a just idea” of the taste. How are these sides connected?

“Isn’t that obvious?” someone may retort: “having an idea of a taste simply consists in feeling or recalling the taste, that is, in undergoing this particular sensation”. But how do we know that someone who has never tasted pineapple (or even a lab-made imitation) will never in fact experience this particular sensation? How are we to exclude the possibility, say, that certain neurological conditions will cause a person to have precisely this sensation when eating cucumber or shrimp, or whatever? Similarly, can we be sure that a congenitally blind person will not in fact have an impression of red and blue dots swimming before him?

The point is that this would make no difference. What matters is that these individuals would have no way of connecting their sensations with the taste of pineapple or with the colours red and blue. (I’m not committing myself on what it would mean actually to attribute experiences of this kind to someone.) The importance of the event of tasting pineapple or seeing an actual coloured object does not lie in its causal efficacy in bringing about a particular sensation; it lies in its constituting a point of reference which guides the speaker in her use of the words - provided of course she knows (e.g. has been told) what she has been tasting or seeing.

What matters are not her mental contents, but the fact that from now on we expect her to be able to carry on certain tasks or to make certain kinds of judgment. Differently put: someone who has seen a red object or has tasted pineapple has access to a sample to which she may appeal in her use of words. She has a mastery of the language-game that someone who has not had these experiences or is incapable of having them does not have. I can tell the first person certain things that I cannot tell the second. (Of course, it isn’t that I can tell the first but not the second what pineapple tastes like - but the first will understand me if I say that something else tastes like pineapple, while the second will not.)

On samples as tools of the language, see Wittgenstein, Philosophical Investigations, §§ 16, 50, 56.

Could this line of thought be applied to the case of horrendous experiences? Are we to think, say, of the loss of a loved one as a “sample” that can be used as a point of reference in describing or comparing experiences? Maybe in some cases, but for the most part, the contexts in which we speak about experiences like grief are radically different from the contexts in which we discuss colours or tastes. I hope to return to this question.

(These reflections were inspired by discussions with Olli Lagerspetz.)


  1. There are obviously close connections between the various discussions you have started here. While the following remarks relate specifically to the discussion of Hume’s remark, the others are, I guess, at the back of my mind at the same time. What I say is primarily an attempt to get clear on some fairly basic points, and may well involve no real disagreement at all with anything you say.

    You ask: ‘But how do we know that someone who has never tasted pineapple (or even a lab-made imitation) will never in fact experience this particular sensation?’ Might it be worth distinguishing two questions here? The first would be of the form: Even if Hume is justified in his confidence that this doesn’t normally happen, does this give him adequate grounds for judging that it never could happen? The second question would be of the form: How could one ever know of any individual who has not, for example, tasted a pineapple that he has not had the relevant sensation? In Hume’s terminology: How could one ever know of any individual who has not had that impression that he has not had the related idea? (The difficulty is, I think, as acute in relation to my own experience as it is in relation to anyone else’s.)

    You comment: ‘The point is that this would make no difference’. This remark should, I take it, be read as an objection to Hume. On Hume’s view it is crucial to the question of whether two people understand each other whether they have the (capacity for) the same ‘ideas’ (conceived as a form of internal representation); and the importance of, for example, having actually tasted a pineapple lies in its necessary causal role (as Hume sees it) in bringing this about. Your response is to suggest that it is not in this instrumental way that having actually tasted a pineapple is important. Its importance lies, rather, ‘in its [my having tasted a pineapple] constituting a point of reference which guides the speaker in her use of the words’. But putting the matter like that seems to me to leave rather more open than one should the possibility of still viewing the situation in instrumental terms: having actually tasted a pineapple is not (as Hume suggests) crucial to mastery of a certain area of our talk on account of its causal role in bringing about certain ‘ideas’; it is crucial, rather, on account of its causal role in generating the ability to carry on certain tasks or to make certain kinds of judgment. To which we might respond with an analogue of your question to Hume: how do we know that someone who has never tasted pineapple will never in fact have this ability?

    These remarks may involve a misreading of what you have in mind here. The notion of a ‘point of reference’ may suggest, or is at least consistent with, a rather different picture: one in which the importance of actual experience (having tasted a pineapple, having lost a loved one) is not merely instrumental. Particular historical events, things I, or we, have undergone, may themselves enter into my exchange with another: as when, in an obvious kind of case, I liken something going on now to something that we jointly encountered in the past. (The Humean thought – that the significance of the past experience must run through some effect that it has in the present – can be very hard to resist.)

    To be continued.

    1. There are, of course, strong connections here with the other discussions you have started. I might relate it briefly to your discussion (which I like) of the idea of ‘capturing an experience in words’. I suspect that we really struggle not to think of this in essentially Humean terms. You articulate the kind of thing I have in mind when you speak of the idea that, if the speaker is successful, ‘the audience will undergo something similar to the speaker’s original experience’. I don’t think (I am not completely certain) that, in what you go on to say, you are suggesting that we should be hesitant about dismissing that. But I am strongly inclined (right now) to say that that way of presenting the matter is just wrong: and that the work needed here is to try to bring into focus what it is a misfired attempt to pin down. I think it possible that working with ‘the taste of pineapple’ and ‘the loss of a loved one’ along side each other could, up to a certain point, be helpful here: in both cases there may be a, similar, philosophical struggle to do proper justice to the importance of a shared history. (You speak of cases in which we might think: ‘No words can do it justice because speaking cannot do it justice’. I have an idea that this might be a helpful way to get a better hold on the issues – but I don’t, at the moment, have any very specific ideas about how it might be pursued.)

    2. The latter is what I was trying to say: my having tasted pineapple is important because it allows others to think of me as someone who can legitimately invoke the taste of pineapple as a point of reference (of comparison) in describing the taste of something or other. I wasn't thinking in terms of some causal effect of a past experience.

    3. Reply to David 3

      Again, I agree with you here. I certainly don't want to say that what the listener undergoes is directly relevant to whether she will be said to have understood what was said. Understanding what you felt is not the same as having that feeling myself, though it may of course MAKE me share your feeling.
      Putting it bluntly, understanding is a matter of what a person is able to do, not of what she is experiencing. (If this sounds too blunt, we should consider that the ability in question may be something rather subtle; it may show itself, say, in the expression with which I listen to what you're telling me, or the tone of voice in which I respond to it).
      Comparing the case of the taste of pineapple and to that of the loss of a loved one - or some other life-shattering experience - might perhaps be useful in order to get clear about the role of a shared history - but if so, I suppose, mainly for bringing out the differences.
      The pineapple problem is mostly just a philosophers' problem - though one can imagine cases in which the ability to taste pineapple would matter practically. (If someone is allergic to pineapple, it might be useful for someone else to taste a dessert for him to find out if it contains pineapple. A more fanciful case: suppose food were used to convey secret messages. Adding pineapple might signal that an attack is imminent from the direction of the West Indies. In that case, it would be important to have a decoder who had actually tasted pineapple, or at least a reasonable simulacrum.)
      Sharing a history may matter greatly in some other cases. It is said that, for people who have been subjected to torture, the hardest part is returning to normal life, since they feel that others have no way of knowing what they've been through. This is undoubtedly an adequate expression of how they feel. But it is not easy to spell out the nature of this attributed ignorance.
      The survivors' feelings MAY to some extent be conditioned by practical experiences: they may discover that people who are not torture survivors, or who haven't worked with torture survivors, are awkward in dealing with their feelings and reactions. But it may also be more of an existential response: the survivors may simply have the feeling of a gap between others and themselves (just as they may feel that there is a gap between their former selves and their present selves). Here the distance between the survivors and other people, as we might say, is existential or ethical rather than intellectual. (I shall return to this problem later.)