H. P. Grice on Reichenbach

On the assumption that this or that problem which originally prompts this or that
analysis is at least on their way towards independent solution, Grice turns his attention to the possibility of providing a constructivist treatment of [things] which might perhaps have more intuitive appeal than a 
realist approach. 

We begin with a class H of 'happenstance-attributions', which
will be divided into 

*basic* happenstance-attributions, i.e. ascriptions to
a subject-item of an attribute which is METABOLICALLY EXPRESSIBLE, and 


*resultant* happenstance-attributions, in which the attributes ascribed, though
not themselves metabolically expressible, are such that their possession by a
subject-item is suitably related to the possession by that or by some other
subject-item, of attributes which _are_ metabolically expressible.

The members of class H of happenstance attributions may be used to SAY what
'happens' (or 'happens to be the case') without talking about any special
entities belonging to a class of happenings or happenstances."

Grice's next stage involves the introduction of the an operator, "...consists of the fact that..."

This operator, when prefixed to a sentence S
which makes a happen-stance attribution to a subject-item, yields a PREDICATE
which will be SATISFIED by an ENTITY which IS a happenstance, provided (a) that
sentence S is true, and (b) provided that some FURTHER METAPHYSICAL CONDITION
obtains, which ensures the metaphysical NECESSITY of the introduction INTO
REALITY of the category of happenstances -- thereby ensuring that this new
category is not just a class of fictions.

As far as the slingshot fallacy (and the 'hideous consequence' that all
facts become identical -- to one Great Big Fact), Grice comments:

In the light of a defence of Reichenbach against the realist attack, I can
perhaps be reasonably confident that this metaphysical EXTENSION OF REALITY
will NOT saddle us with any intolerable paradox.

 pace the caveat that to some the slingshot is not contradictory in the sense that a paradox is, but
merely an unexpected consequence -- not seriously hideous, at that. 

What the metaphysical condition mentioned above would be
which would JUSTIFY the metaphysical extension remains, alas, to be determined. 

It
is tempting to think that it would be connected with a THEORETICAL NEED to
have happenstances as items in, say, causal relations.