Some people including myself, suggested that ultrarunning is some sort of extension to hiking. Just as if hikers progressively build up their walking pace and end up running. I think this is actually only partly true. It depends how and why you like hiking.

The hare

I've noticed that during most of my hiking trips, I try to see as much scenery and attractive features as possible in the given time. This leads to walk fast, climb up to the summits and dive down to the gorges and lakes. There are clear spatial and temporal objectives, set more or less consciously. I want to climb up this mountain, I want to sleep at this lake tonight, etc ... To some extend, this is fairly similar to race conditions, where I want to pass this checkpoint at that time, etc ... Everything is planned beforehand and I'm adrenalin-driven towards a set of objectives. I'm not running, but I'm already a hare in my mind.

The tortoise

Another way to hike is not to bother too much about location and time. Just walk and see. Change plans on the way. Add extra detours. Rest somewhere for sometimes. This approach is advocated by many hiking guide books. Believe it or not, this happens to me as well. When I'm depressed and I don't have the mental energy to chase after an objective. Or when I see the end of a multi-day hike approaching and I don't want to rush it anymore, to stay longer. Being the tortoise is not as easy as might look. Because less planning also means more uncertainty that could potentially lead to stress if not well handled.

The tortoise approach is not reserved to hikers, though. Many non-competitive ultra-runners are also tortoises in their mind. This typically happens when you don't have a time objective in mind and want to enjoy the scenery. The race is there, but not considered as such. It's an aid to the run (water stations, route marking, massages, ...) and a nice way to meet like-minded people. It's worth noticing that many hares on the UTMB reduce this event exclusively to a competition and suggest tortoises to run around the Mont-Blanc at another date if they're not happy with it. They completely miss the point and just don't see that the event is much more than a race.
Some event organisers already caught this trend. Many ultra-races are open to tortoises, with a fairly long time limit. Even some marathons now welcome walkers by extending the time limit to 8 hours.

Being hare or tortoise is not so much a matter of physical capabilities in the end, it's mostly a mental state. Hares can hike and tortoises run.

Tortoise and hare
Tortoise and hare in summer 2005

The hare's need for symbols

Whether it's hiking or running, the hare approach often needs strong symbols. Such symbols push people forward by supporting and augmenting the objectives. They add extra motivation on adrenalin-driven races and create virtual objectives on hiking paths. They could be for example running from a city to another, cross a mountain or follow a river. These symbols are one of the reason why races such as the UTMB became so popular so fast: around the highest mountain in Europe, across 3 countries... These same symbols drove lots of attention and admiration to the "Tour du Mont-Blanc" long-distance hiking path before the race was first organised. For example it was described on TF1 (a French populist TV channel) as one of the most famous and hardest hiking path. This is clearly not true. While it's not an easy path, several French long-distance hiking paths are technically harder (GR54 and GR20 to give only 2 names), not even considering the rest of the world... This shows how the symbols can augment the physical reality of a hike or a run in the hare's mind.

A symbol I quite like is to join two places with my feet. Modern transportation methods are more or less a form of teleportation, as you are very little involved in the navigation and certainly not immersed in the environment. And you miss a lot. The world is not continuous anymore, but made of a set of discrete points. Running or hiking makes you feel like you reconnect these points, and gives a very good feeling of belonging to this continuous space. While running from London to Brighton for example, I've seen every meter of ground in between the two cities. Note that this also applies to smaller scales; for example walking in cities instead of taking the tube.

The tortoise's need for simplicity

On the other hand, the tortoise seeks for the simplicity of the journey. Running and walking are simple activities by essence. Simplicity can mean various things depending on the context and person. Hiking with a tent makes things easier, as you are free to sleep wherever you want, thus reducing the need for planning and reaching objectives. Sleeping in refuges also simplifies things, as there is less equipment to carry and you get to meet more people.

The best of both world

And often hikers/runners are tempted by both the hare and the tortoise. I've been thinking of running the whole length of the Thames (300km) in one leg. This is the most extreme option (at one end of the scale) that would probably take between 40 and 50 hours. In order to see more landscape and therefore run during daylight only, I've also thought about splitting the journey into 3 consecutive running days of about 100km. This is a bit of a softer option. But it still involves major milestones and fair daily mileage. It's still a hare option. Lately, and somehow strangely, I've been thinking seriously about walking along the Thames following a day-to-day basis, without real plan. Without really knowing where and how to sleep the next night. My new very-waterproof clothing may have helped this thought, as it would allow to sleep outside anywhere by virtually any weather and without any further equipment (such as sleeping bag and tent) that requires more careful planning.
Note that running in the rain is often perceived as a form of escape: the hare seeks the finish line to get a hot shower. Hiking in the rain shouldn't be seen as an escape. The tortoise feels comfortable in the rain. The hare mentally projects himself towards the next checkpoint whereas the tortoise enjoys the current moment.

The same person can clearly be hare or the tortoise or anything in between at a given time. Now, is it possible to become simultaneously the hare and the tortoise? Get the best of both worlds? I'm actively looking after that. I don't think I've reached this stage yet. This probably requires a bit more experience too ...

Ultra confused.