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Monday , 20 th December 1858. 
Professor CHRISTISON, V.P., in the Chair. 
The following Communications were read : — 
1. On the First Properties of Matter — Inertia, Gravitation, 
Elasticity — referred to a common Law. By John G. 
Macvicar, D.D. Communicated by Professor Fraser. 
The author commences by a vindication of the Scottish philoso- 
phy, that he may legitimately build upon substance as a reality as 
well as phenomenon. He then shows that just as the idea of sub- 
stance presents, a priori, an alternative, viz., those which are wholly 
fixed, the subject of law imposed from without only, and those which 
possess a power of changing their mode of being from within them- 
selves ; so, in point of fact, common observation has recognised in 
all ages two orders of substances or beings characterized by this 
difference, and filling up in the sphere of reality this alternative 
given by pure thought; the one being the ground of all natural phe- 
nomena, and ordinarily designated body ; the other the ground of 
all moral and intellectual phenomena, and designated spirit. 
Of Body the most characteristic properties are inertia, gravita- 
tion, and elasticity ; and these are still regarded in science merely 
as postulates, and that, unrelated to each other except as properties 
inhering in the same subject ; just as heat, electricity, magnetism, and 
chemical affinity were some years ago. It is the attempt to show the 
homogeneity of this group of properties, and to account for them, 
that has given its title to this communication. 
For this purpose the author lays hold of The Law of Assimi- 
lation , already admitted in physiology ; he shows that it operates in 
nature far more extensively than is generally supposed ; in fact, he 
affirms that it is universal, and the only law of nature that needs 
to he considered by us for the explanation of phenomena. This 
law, when thus conceived in its utmost generality, he thus ex- 
presses : — “Everything tends to assimilate itself to itself in suc- 
cessive moments of its existence ; and extends this action to all 
things around to unknown distances, assimilating them also more 
or less to itself, meanwhile being of course more or less assimilated to 
