Quote of the Week: Jeffrey on Desirability

“It my indeed by that I desire something, and later, when I have it, find it not as good as I had thought. This is a case where my judgement of desirability have changed as a result of experience.”  – Richard Jeffrey. The Logic of Decision. p. 63

I am currently rereading Richard Jeffrey’s classic The Logic of Decision to refresh my knowledge of decision theoy and this passage caught my eye. It occurs in a discussion of whether we can desire something we have (or believe to have) and amounts to little more than an aside. For a quote of the week it might seem less than exciting, but it surprised and excited me.

The formulation is not entirely clear, but Jeffrey appears to suggest that a desire is a judgement that something is desirable. The goodness of the thing appears to come first. We learn it through experience and adapt or at least should adapt our desires to it. Our judgements of desirability are proven wrong, if things are less good than we thought. It is not just that we found out that we have different desires than we thought, rather our judgements of desirability are proven wrong by experience.

This picture conflict with the kind of non-cognitive Humeanism I would have assumed to find in a book on decision theory. I would have assumed that Jeffrey presents desires not as a form of judgement and that the goodness of objects would not guide the desires. Desires would be practical states conferring the desirabaility to objects. Instead I found this surprising quote, which reminds me more Elijah Millgram’s work on practical reasoning.

Sadly, I am still catching up on decision theory and lack acquaintance with Jeffrey’s later work. I do not know yet whether this quote conflicts with Jeffrey’s other contributions or whether it fits in.

Unpreferred Happiness and My Mother’s Grandchildren

This post is about whether we sometimes do not prefer happiness and whether my mother should want me to procreate. In a dinner conversation my mother stated that she would be happy if I had children, but does not mind if I do not have children. Her point was that my procreation is up to me and she does not want to act in any way to increase the likelihood of me having children.

As I see it, my mother made two claims:

  1. My mother would be happy if I had children.
  2. My mother is not motivated to make me get children.

How can one make sense of my mother’s position within decision theory? A natural interpretation of claim 1 would be to say that my mothers desirability value for me having a child (C) is larger than zero (C > 0) – after all the child would make her happy – and the desirability for me having no child (~C) is equal zero (~C = 0), since there is no happiness or unhappiness associated with no child.

This interpretation, however, results in a contradiction with claim 2 that she does not want to do anything to increase the likelihood of me having children. After all, if C > 0 and ~C = 0, then C > ~C and there should be some prize my mother should be willing to pay to increase the likelihood of procreation. But I took it that my mother is not motivated to make me get children! Either my mother is irrational and should perhaps actively try to get me to have children, or something with my interpretation is wrong. Continue reading “Unpreferred Happiness and My Mother’s Grandchildren”