1 XI
2 that they were benevolently endowed by nature with
3 their nauseous flavor to warn us against the danger
4 of using them too freely.
5 A physician might as rationally assert, that it is
6 possible for him to give to the rotation of the earth
7 any direction he wills, as that the remedies he admin-
8 isters in accordance with the mere custom of the
9 profession, must infallibly prove beneficial. He cannot
10 dictate laws to Nature in either case ; experience alone
11 is the teacher and arbiter, and on experience must
12 we ground our hopes. But, as hope often deceives us;
13 and as even the most skilful physician is not infallible;
14 the grand rule to be adopted is — “ all strong doses to
15 be avoided, and such only to be administered as, though
16 they may not benefit, yet, cannot do any harm .” This
17 rule may easily be followed, if we acquaint ourselves
18 with the effects of medicines both in large and minute
19 doses ; and I think, that without this knowledge, no
20 physician can prescribe any remedy whatever, with a
21 clear conscience. The point to which I devoted the
22 greatest attention in my investigations, was — observing
23 the effects produced by various medicines ; and it was
24 not until the operation of a prescription had been
25 thoroughly tested, that I felt confidence in prescribing
26 it in similar cases — similia similibus.
27 The ancients, without being acquainted with the
28 natural law of similia similibus curantur (according
29 to which small doses are required) were well aware
30 of the injurious effects of large doses, and recom-
31 mended the greatest caution — Praestat pauca dosi, ct
32 per intervalla remedia exhibere, quam uno impetu ven-
33 triculum remcdiorum molcsle obrucre ; i. c . “It is better