22. The conclusion in this argument is that increased vigilance by drug enforcement
, A6 K8 z, {& G% C$ |( o) b' [authorities has resulted in an increase in the illegal use of cocaine. The author reaches , x0 G- j0 |# e, m
this conclusion on the grounds that drug traffickers have responded to increased S$ Z- X+ r3 i8 R* |! e; l
enforcement efforts by switching from bulkier and riskier drugs to cocaine. Presumably,
+ S( p) J8 r3 e7 B9 j2 D' @the author's reasoning is that the increased enforcement efforts inadvertently brought
0 s. z! D6 v9 c. z& X/ wabout an increase in the supply of cocaine which, in turn, brought about the observed 1 \9 G: t% t k& B L1 h8 d ^2 @
increase in the illegal use of cocaine. This line of reasoning is problematic in two ; U6 x! p" s9 x+ Y. B
important respects." e) O- w- |; V5 |
In the first place, the author has engaged in "after this, therefore because of this" 0 k9 Q: W- _5 [. f! n' [! h: v7 B( {
reasoning. The only reason offered for believing that the increased vigilance caused the " N: W7 `! j- `, \# M4 l% s4 D1 B
increase in cocaine use is the fact that the former preceded the latter. No additional
9 d% O) Q7 `4 O; n* H4 fevidence linking the two events is offered in the argument, thus leaving open the
# k& q8 W+ R/ H o' P2 f2 d5 ~* Wpossibility that the two events are not causally related but merely correlated. This in turn
5 u0 p3 z7 d$ p7 ?' dleaves open the possibility that factors other than the one cited are responsible for the # C @$ x$ S% m
increase in cocaine use.
$ p9 H2 f0 e3 S# s2 V z In the second place, the author assumes that an increase in the supply of cocaine is ) b' L. q" g+ X$ J
sufficient to bring about an increase in its use. While this is a tempting assumption, it is . D6 j R) E# p' i
a problematic one. The presumption required to substantiate this view is that drug users 2 a* D6 t! [/ k; u3 D' K: n
are not particular about which drugs they use, so that if marijuana and heroin are not ) O- l+ ?7 l: ?
available, they will switch to whatever drug is available—cocaine in this case. The % D' x2 s$ `8 |
assumption does not seem reasonable on its face. Marijuana, heroin, and cocaine are not & Q9 F* j& U% Q& \8 I
alike in their effects on users; nor are they alike in the manner in which they are # W# i! T" D% i# J8 S* }1 b+ p0 e
ingested or in their addictive properties. The view that drug users' choice of drugs is
) k) q! g( S E1 z6 c$ Y7 Q6 @4 Rsimply a function of supply overlooks these important differences.
4 U. z/ u+ N9 M In conclusion, the author has failed to establish a causal link between increased ; ]# I4 X5 @# P( |3 ]5 l
enforcement efforts and the observed increase in illegal cocaine use. While the 9 @, i! s Z% M2 r& z1 H
enforcement activities may have been a contributing factor, to show a clear causal + \7 Z% c0 X2 p, \, Z- K
connection the author must examine and rule out various other factors. |