Dogs are the gods of frolic. I don't remember who said that, but it is true. They are classic optimists: no matter if they've chased birds and squirrels for years unsuccessfully: each time they spot one or the other in the yard they give chase. "Maybe this time," they seem to grin, "the birds won't have wings. Maybe this time I'll beat the squirrel to the tree." Never mind that they never do. There's always next time.
Of course, this may be because while they hold the memory of smells in their brains for decades, they don't seem to hold much else. They certainly don't hold grudges or pout from injustices. Pat a dog and he will forget that you smacked his nose for robbing the garbage can an hour before.
I don't think they hold guilt either. Or anticipation of consequence of behavior. If they did, would they rob the same garbage can an hour later even after you screamed at them and smacked their noses? Dogs aren't stupid, not at all. it's just that they mostly live in the moment. When a moment is over with it's delightful garbage feast its over. When the screaming session as you clean the kitchen floor is over its over. There's a bird in the yard isn't there? Let's go!!
They do hold patterns in their brains, definitely. That's how they recall what to do when they spot a piece of agility equipment even if several years have past. They have an innate sense of time patterns, too. I don't understand how they know exactly when its time for their feeding bowls to descend to the kitchen floor full of their favorite kibble, or when its time for the school bus to drop off the kids, but they do. Even when daylight savings time changes the hour.
Dogs have a pretty big vocabulary for human words. If there's something of canine interest attached to the word. Such as walk, dinner, biscuit, dog park, car ride, cat, bird, squirrel, etc. They are not as good with words like come, no, bad dog, leave it, but they will learn them eventually after you've worked up a pretty good headache trying to teach them.
Dogs tend to have pretty short attention spans, actually. The 'in the moment thing again' probably. They get bored easily. They need something to do to keep them busy, happy, and out of garbage cans. Unfortunately modern dogs are primarily pets and their original functions denied them. Which accounts for a lot of the garbage cans runs. Or maybe they would make time for those anyway. Who knows.
Dogs do worry, they do form strong attachments to people and other animals. They do grieve. Perhaps this is more that they like patterns than that they are thinking of the missing person or animal. Maybe it is because they are pack animals. I have lived with dogs all my life and I don't really know.
Dogs are heroic. They will give their lives to protect an owner or a pack member. Dogs are infinitely patient. Anyone who has lived with dogs knows this for truth. For these things and for their ability to live in the moment and roll with life's punches without holding grudges, we humans should give thanks and emulate them.
Dogs will not desert you because you make a mistake or lose your job or your house. Just throw the ball for them and they're happy. Dogs don't care if you are young or old or fat or thin, beautiful or ugly. It all smells the same anyway. Just be kind to them and they will be at your side no matter what comes. Can't say that about people mostly.
So, they track in garden dirt, chew the tassels off the oriental rugs, and might have the occasional flea. So you have to give up brocade bedspreads and light colored upholstery. So what. We will not mention overturned garbage cans here... or chewed up shoes either. Dogs will tackle a burglar, warn you of an impending storm, and make you laugh with their clowning around. Their footpads smell like popcorn, they are great to cuddle up to for an afternoon nap and they are always ready for the next adventure.
They are not called man's best friend for nothing.