I've been a huge Bonanza fan since the 1960s and this is definitely one of the 10 best episodes from the series (Along with most of the Ben wife flashbacks, the episode "Hayburner", and a few others). In this classic comedy tale, character actor Arthur Hunnicutt (who basically, always played himself) has a lazy hound dog named Walter. The dog barely moves throughout the entire story yet Hunnicutt will spout off lines like "I haven't seen Walter this excited since he was a pup." The story is also one of the classic Bonanza themes of Hoss having that innocent trust of others that gets him sucked into something he shouldn't because of it (Little Joe, of course, certainly knew how to use this against him and it's one of the reasons everyone loved Dan Blocker as Hoss). At first, Hoss doesn't understand the so-called feedback that Hunnicutt gets from the always inanimate Walter, but by the end of the story, Hoss has become a Walter interpreter, too -- to the amazement of the rest of the Cartrights. This episode even inspired a sequel that was almost as good as this original.
Personal note: My live-in girlfriend in 1980 had a small female puppy for awhile. I don't remember the dog's actual name but I always called her Walter (in honor of this episode).