Archives For Adam Morton

Author Information: Adam Morton, University of British Columbia,

Morton, Adam. “Could It Be a Conditional?” Social Epistemology Review and Reply Collective 7, no. 10 (2018): 28-30.

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Chris Tweedt proposes that there is no independent concept of contrastive knowledge. He allows that we can meaningfully and in fact helpfully say that a person knows that p rather than q. But this is shorthand for something that can be said in a more traditional way as that the person knows that if p or q then p. I have two worries about this line. First, I do not know how to understand the conditional here. And second, I suspect that the suggested interpretation takes away the motive for using a contrastive idiom in the first place.

What Kind of Conditional?

So, could “Sophia knows that it is a goldfinch rather than a canary” mean “Sophia knows that if it is a goldfinch or a canary then it is a goldfinch”? What could “if” mean for this to be plausible? The simplest possibility is that it is a material conditional. But this cannot be right.

Sophia, who knows very little about small birds, sees an eagle land on a nearby high branch. From its size and distinctive shape she can tell immediately that it is a large raptor and not a little seed-eater such as a goldfinch or canary. That means she will know that “(Goldfinch v Canary) É Goldfinch” is true, because she knows that the antecedent is false. For the same reason she will know that “(Goldfinch v Canary) É Canary” is true. But surely she knows neither that it is a goldfinch rather than a canary nor that it is a  canary rather than a goldfinch, and more than surely not both.

Perhaps then it is a subjunctive (counterfactual) conditional: if it had been a goldfinch or a canary then it would have been a canary. I suppose there conceivably are circumstances where a high-tech procedure could transform a bird embryo into one of a different species. It might be that the most possible such procedure can transform bird embryos into canaries but never into goldfinches. Suppose this is so.

Now suppose that Sophia’s cousin Sonia is an expert ornithologist and knows at a glance what species the blue tit a metre away is. But she also knows about the embryo-transforming procedure so she knows that if it had been a goldfinch or a canary then it would have been a canary. So she knows that it is a goldfinch rather than a canary? Of course not.

The remaining possibility is that it is an indicative conditional. For many philosophers these are just material conditionals, so that won’t do. But for others they are a distinct kind. One way of paraphrasing the resulting interpretation is as “if it turns out to be a goldfinch or a canary, it will turn out to be a goldfinch”. This is still not suitable. Suppose Sonia knows immediately that it is a blue tit but is dealing with an ignorant person who doubts her judgement. She admits that there are other things it could on closer examination — which in fact is not necessary — turn out to be.

And then goldfinch would be more likely to result than canary. So she accepts this particular indicative conditional (if goldfinch or canary then goldfinch.). But she too does not know that it is a goldfinch rather than a canary, because she knows it is a blue tit. (For the differences between kinds of conditionals see Jonathan Bennett A Philosophical a Guide to Conditionals. Oxford: Clarendon Press, 2003.)

Understanding the Contrastive Idiom

These may be problems about formulating the claim rather than about the underlying intention. However I do not think that any version of the idea that all uses of “knows that p rather than q” can be represented as choosing the least wrong from a list of alternatives will work. For one use of the contrastive idiom is to describe limitations in a person’s ability to distinguish possibilities.

Consider four people with varying degrees of red/green colour blindness but with otherwise normal human colour-distinguishing capacities. (Sorry, it has to be four. For the distinctions see

Alyosha has normal r/g vision;

Boris partial capacity (say 70% of normal);

Yekaterina limited capacity (say 40% of normal);

Zenaida no r/g discrimination at all.

They are each presented with one of those familiar colour charts, one in which the most salient figure 3 in vivid green is completed to 8 in dull orange against a background of orangy murkiness. Alyosha knows that it is a 3, so that it is 3 rather than 7 and that it is 3 rather than 8. As a result he knows both that if it is 3 or 8 it is 3 and that if it is 3 or 7 it is 3. Boris can see that it is either 3 or 8; he is not sure which but thinks it is 3.

So he knows that it is 3-or-8 rather than 7 but not that it is 3 rather than a 7 (since for all he knows it might be 8 rather than 3). He also knows that if it is 3-or-8 or 7 then it is 7, and that if it is 3 or 7 then it is 3 (since the antecedent of the conditional rules out 8). Yekaterina thinks that it is 3 or 8, but she has no idea which. She knows that if it is 3 or 7 then it is 3, and that if it is 8 or 7 then it is 8, but nothing more from these possibilities.

Finally Zenaida. She hasn’t a clue about anything needing r/g discrimination and has none of this knowledge. I am assuming that all factors except for r/g discrimination are favourable to knowledge for all four people.

All of these descriptions are natural applications of the “knows rather than” construction in English. They show a fine-grained transition from full contrast to none and in particular that the “if p or q then p” versions appear and disappear at different stages in the transition than the “p rather than q” versions do. That is the point of the contrastive construction, to allow us to make these distinctions.

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Bennett, Jonathan. A Philosophical a Guide to Conditionals. Oxford: Clarendon Press, 2003.

Tweedt, Chris. “ Solving the Problem of Nearly Convergent Knowledge.” Social Epistemology 32, 219-227: (2018).