The assignment for our class is different from that for Whiteley's in several respects. So go by this, not by his list of questions.

- 5.3.3 b.

(I did not say this in class on 29 January, but a SYMLOG printout is preferable here.) - 5.4.1 b.

Note that this true-false statement has an*understood***"For ALL \alpha, ..."**at the beginning of it. So, in line with my remarks in the posting to our discussion list a week or two ago, you must give a general argument for the truth of this statement if you say it is true, whereas if you say it is false, then a single specific counterexample is enough to support your claim of falsehood. - 5.4.4 f.

Give a SYMLOG printout of an SD-derivation that derives both \alpha and \not \alpha, for some wff \alpha of your choice. - 5.4.5 d.

Again, give a SYMLOG printout. And of course you will have to understand precisely the definition (in class and in the book) of "SD-inconsistent", and also the "Test for Derivability", before you even know what your printout should contain.... :-) - 5.4.7 h. (yes, SYMLOG printout again)
- For each of the arguments in (a) through (b) below,
(i) give an SD-derivation (SYMLOG printout) of the conclusion from the premise(s), and

(ii) give an English argument that, as closely as possible, paraphrases the SD-der. you gave in (i). (Examples of what I mean here will be given in class.) It may be fair to say that what I do when I have to construct a derivation is to map out an English version of it first; I certainly think in English rather than in SD! :-)

(a) A -> B (b) \not A v B (c) ---------------- ---------- ---------- \not B -> \not A A -> B A v \not A