Have you ever seen a Thoroughbred run free in an open pasture? It's one of life's most magnificent sights.
However, keeping a Thoroughbred requires acres of land and globs of financial resources, both of which are beyond the average person's means. You could, of course, visit a ranch that raises Thoroughbreds. If you're lucky the owners might grant you the privilege of watching their horses run about.
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Five-day-old Thoroughbred running. See original photo here.
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Mature Terrier running with a ball. See original photo here.
On the other hand, have you ever seen a terrier run free in an open field? It's another of life's magnificent sights. And it's a spectacle even a person of average means can experience.
Not that keeping a Terrier is cheap, but keeping a Terrier is a lot less expensive than keeping a Thoroughbred--and yet Terriers are just as thrilling to watch run.
Terriers are the poor person's Thoroughbred.