ISSN 0226-1448 

inforrnal logic 
newsletter news lett newsletter newsletter 

Unhf~. 
-· ... '1 of ~;ndlOt 

f JUL 28 1981 
vol. iii, no. ~ eds., J. 

contents 

ARTICLES 

Worries About.~'Quo~e as a Fallacy 
Trudy GOvl..er ... " ..... "." .... """ " ........ " " 2 

Charity Begins at Home 
Ralph H. Johnson ••••••••••••••••• 4 

Ad Hominem and Ad Verecundiam 
- P. J .. Mackenzie ......... ' ...................... ".. 9 

Part/Whole Fallacies 
Nelson Pole ............................ " .............. o 11 

CRITICAL REVIEWS 
Toulmin's Bold Experiment 
(second part) 

Ralph H. Johnson ••••••••.•.•••••.• 13 
Baum and Engel 

Nicholas Griffin .•••••••••..••.••. 20 

DISCUSSION NOTES 

More on the Surprise Test Puzzle 
Peter Galle •...•••..••..••••.••••• 21 

CONFERENCE REPORTS 

First National Conference on 
Critical Thinking, Horal Education 
and Rationality, Sonoma State 
(!1ay 1980)............................ 22 

ANNOUNCEMENTS. • • . • • • • • . • • • • • . • . • . • . • • • • • •• 24 

QUERIES. • . • • • • • . • • • • • • • • • • • • • • • • • . . • • • • . •• 25 

CORRECTION. • • • • • • • . . • • • • • • • • • • • • • • • • • • • • •• 25 
CONTENTS OF JOURNAL ARTICLES ••••••••••••.• 26 

JOURNAL CONTENTS.......................... 26 

BOOKS RECEIVED............................ 27 

TIDBITS •.•••••••••.••••••••••••••.••••..•• 28 

June 1981 

from the 
editors 

We are pleased to present three articles on 
fallacies in the current issue, by Trudy 
Govier, P. J. Mackenzie and Nelson Pole, plus 
a discussion of widely invoked "Principle of 
Charity", by Ralph Johnson. Note too the 
second (and final) part of Ralph Johnson's 
critical review of Toulmin, et al., An Intro-
duction to Reasoning. The footnotes~o-ootn 
parts of-Yohnson's review are included at the 
end of part two: footnotes 1-9 belong to part 
one: the remaining ones, to part two. eWe 
apologize for the inconvenience to readers.) 

A new department is introduced on page 26: 
abstracts of articles on informal logic that 
have appeared in other journals. Help us to 
keep this department complete and up to date 
by sending in an abstract of anything you pub-
lish elsewhere, or failing that, an offprint 
of your article, or (third best but still good) 
a note indicating the title and when and where 

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it appeared. This will help you reach a wider 
audience, and help other readers to keep a-
breast of work in the field. 

~1ake a note of the (Second International) 
Symposium on Informal Logic, tentatively sched-
uled for June 20-21-22-23, 1983 at the Univer-
sity of Windsor. The time will be ripe for a 
review of the progress of the informal logic 
movement since the first Windsor symposium in 
June 1978. Wi th. two years t lead time, we hope 
there will be ample opportunity for people to 
work up papers. We herewith issue the first 
call for papers. Papers on any and all topics 
related to the theory and teaching of informal 
logic are welcome. Inexpensive on~campus ac-
commodations and meals will be available. We 
will keep you posted as more detailed plans 
develop. 

Hith this issue we complete the third year 
of publication of the Informal Logfc Newsletter. 
The Newsletter has tripled, since 1ts first 
year, in the amount of material included. We 
are sorry that the increase in the amount of 
material, plus rising costs, have prevented us 
from issuing an Examples Supplement with this 
volume: we have simply run out of money. 
However, we do have a supply of examples--many 
with accompanying analyses·-on hand, and we 
will be printing as many of these as we can in 
the Fall 1981 number (Yol. iv, No.1) which 
will be coming out early in the fall--in time 
for first~semester courses. It would help a 
lot if you would comb your last-year's stock 
of examples, and this summer send us a few 
juicy ones for inclusion in that issue. In-
clude your own [succinct) analyses of them if 
you can. 

Note that subscription renewals are now due. 
It has been necessary to increase our rates to 
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hope you will agree that this is still a mod-
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Have a pleasant summer. * 
Thanks to Vi Smith and ~lidge Mailloux for 
typing this issue. Without the (unpaid) edi-
torial and production assistance of June Blair, 
this issue would not have seen the light of 
day~ we are grateful for her help. Our t2n-
aging Editor, Peter tiilkinson, leaves for a 
well-earned sabbatical as we go to press. 

2 

articles 

Worries About 
-r:'u l3uague as a 
Fallacy 

Trud y Govier 
Trent University 

Traditionally, the tu quoque argument has 
been regarded as a kind of fallacious ad 
hominem. A classic form of this consists in 
attacking someone for not practicing what he 
preaches, and then going on to impugn on these 
grounds the content preached. l For example, 
several years ago Ontario and Federal govern-
ment officials in Canada, having exhorted 
Canadians to spend winter holiday money at 
home in Canada, nevertheless abandoned our 
northern country for winter vacations in 
Florida and the Caribbean. From such a dis-
crepancy between preaching and personal prac-
tice, one might be tempted to infer that what 
is preached is false, wrong, or unimportant. 
If one did this, then, traditionally, one 
would have committed an ad hominem fallacy of 
the tu quoque variety. -

One may feel doubts about this case. Some-
how, one feels, critics of government ministers 
have got some kind of valid point here. The 
matter has perplexed me for some time, and I'd 
like either to generate a similar perplexity 
in others'20r to find someone who can rid me 
of my own. 

We may look at such cases in an abstract 
way. A person, A, holds a principle, P, which 
is of the form "People in circumstances of 
type (c) should do actions of type (a)". He 
affirms this principle, communicates it to 
others, advocates that they follow it, argues 
on its behalf, and so on. But A himself, when 
in circumstances of type ec) does not do ac-
tions of type (a)~ he performs, on the other 
hand, actions of type (x)--quite contrary to 
(a)--and thus fails to conform to his own 
principle. Now consider another person B who 
has been part of A's audience on some of-the 
many occasions on-which he has exhorted others 
to conform their actions to P. B, let us say, 
points out to A in no uncertain terms that his 
action of type-(x) is in violation of his own 
principle, P. So far, B certainly has not 
committed any fallacy. -He has merely made a