22. The conclusion in this argument is that increased vigilance by drug enforcement
- `5 X/ I6 @) Yauthorities has resulted in an increase in the illegal use of cocaine. The author reaches , h. L7 m" m5 p2 k+ k
this conclusion on the grounds that drug traffickers have responded to increased $ Q$ K3 u1 Z) ~3 E) S8 V/ v
enforcement efforts by switching from bulkier and riskier drugs to cocaine. Presumably, / j# c8 K/ y) l1 p# S
the author's reasoning is that the increased enforcement efforts inadvertently brought 2 h# Y g8 R4 x0 f0 n
about an increase in the supply of cocaine which, in turn, brought about the observed ! o: _. i& Q) r# j5 }# }* Z2 A
increase in the illegal use of cocaine. This line of reasoning is problematic in two
5 ?# g5 z& s& P& i* Uimportant respects.
% F* j5 m ^' d) {) a( }( ?3 h. v In the first place, the author has engaged in "after this, therefore because of this" . C% V& g. R" |% J7 d) y$ Z
reasoning. The only reason offered for believing that the increased vigilance caused the
" b& [! ~+ I7 P6 C1 P$ Hincrease in cocaine use is the fact that the former preceded the latter. No additional / w& N) \; Z3 ^" |" Q/ O4 d( c
evidence linking the two events is offered in the argument, thus leaving open the
# i# p; `) z+ k7 p3 M/ E: H+ {possibility that the two events are not causally related but merely correlated. This in turn / n) b9 P+ z, J. ]; P$ H3 n+ E
leaves open the possibility that factors other than the one cited are responsible for the 4 A$ k9 x, E; u7 M; d
increase in cocaine use.
; t `1 v& l! F: O& r* L4 M4 F4 L In the second place, the author assumes that an increase in the supply of cocaine is
3 J9 a/ y2 r; a" |sufficient to bring about an increase in its use. While this is a tempting assumption, it is ' C @: Q5 B" s: w2 ]" |5 F2 A
a problematic one. The presumption required to substantiate this view is that drug users # y$ ~, B3 J1 q: \7 ]$ |( W) h. {
are not particular about which drugs they use, so that if marijuana and heroin are not
2 J' D& P) y3 L: xavailable, they will switch to whatever drug is available—cocaine in this case. The
T6 e Q. t- w/ oassumption does not seem reasonable on its face. Marijuana, heroin, and cocaine are not 1 k. m+ B# N$ [! t7 L$ n
alike in their effects on users; nor are they alike in the manner in which they are
# V% Z1 s2 B' I. v2 ?ingested or in their addictive properties. The view that drug users' choice of drugs is
" o* m9 Y, Y x# y' i9 Usimply a function of supply overlooks these important differences.8 C/ e: F& P3 a* Y' v4 O
In conclusion, the author has failed to establish a causal link between increased
, a% \0 o/ Z* b7 h5 k/ E5 lenforcement efforts and the observed increase in illegal cocaine use. While the
8 p" ?) y6 r. P3 Qenforcement activities may have been a contributing factor, to show a clear causal
( s% t1 l' x: m" a. f# }. xconnection the author must examine and rule out various other factors. |
发表于 2012-8-15 21:50:16
