What is the presumption in the context of possession of stolen goods?

This presumption is expressed in Regina v. Suchard, 1956 CanLII 10 (SCC), [1956] S.C.R. 425 at 427, 23 C.R. 207, 114 C.C.C. 257, 2 D.L.R. (2d) 609, in these words: " … the presumption, resulting from the mere circumstance of recent possession of stolen goods, is that the initial possession was gained with the knowledge that the goods were stolen. The fact thus presumed — i.e. a guilty knowledge coincidental with initial possession — negatives the existence of an honest initial possession which is part of the essence of retaining and, hence, necessarily precludes a conviction for the latter offence … "In brief, and once the fact of recent possession of stolen goods is established, the fact that they were gained with the knowledge that they were stolen is immediately presumed". (The italics are mine.)