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Labyrinth Two-Door Puzzle

My partner's favorite movie is without a doubt Labyrinth (1986) and I'm more or less "forced" to watch it at least once or twice a year. Not that I'm complaining. :)

I've always liked the Two-Door Puzzle presented in the movie but I've never really sat down and thought it through properly and my brain is too slow to verify the solution while the movie is running and I often forget about it afterwards.

You all know the drill:

There are two guards each guarding a door. One of the doors leads to the castle and the other one to certain death. One of the guards always speaks the truth and the other one always lies. You may ask one question.

Let A correspond to one fixed door and guard and B correspond to the other guard/door. WLOG also assume that A is the safe door.

One possible solution is to ask guard A which door guard B would say leads to the castle and then choose the opposite door.

We will show that this solution is independent of which of the guards is the compulsive liar.

  • First suppose that guard A is the liar. Thus, by assumption, B always tells the truth. We ask A if B would tell you which door is safe. Since B is truthful they would point you to door A but since guard A is a liar they would say that guard B would point your to door B. By taking the opposite door A we are safe.

  • Secondly suppose that guard A is truthful and that guard B now is the liar. We ask A if B would tell you which door is safe. Since B is a liar they would say that B is the correct choice and since A is an agent of truth they would say that B would point you to door B. By taking the opposite door A we are again safe.

This shows that the proposed solution actually works. I think it's a fun little puzzle.

assorted links [-1]

Visual looming syndrome

Visual looming syndrome is a problem with visual perception that causes people to inaccurately think that a stationary object is moving towards them, and might poke their eyes.

All my life I have experienced actual physical pain in and behind my eyes when looking at sharp, pointy objects and certain 3-dimensional patterns, for instance some radiators viewed from a particular angle. This is a weird sensation and it seems to worsen when I'm tired, having anxiety or when I find myself in a general "fragile" state of mind.

I've had this all my life but I never really took it seriously and I even started to think that this condition was some kind of psychological defect and for a short period of time I even tried to "reprogram" myself to not feel this pain when looking at pointy stuff, without any luck I might add.

For some reason I never researched this and I've never meet anyone else with the same problem, perhaps in part because of my assumption that this is might just be my imagination and or a minor mental disorder so I felt reluctant to bring it up in conversations.

Relatively recently I stumbled upon the Wikipedia page on Visual looming syndrom . It has a name and it turns out that it's not all that uncommon but sadly but there no treatments. Just knowing this thing is real was kind of a relief for me.

Indoor Bonsai

Among bonsai professionals and amateur enthusiasts alike this is considered a controversial topic. It's said that it simply can't be done.

Professional high quality bonsai trees are grown, developed and kept outdoors at all times, with very few exceptions.

Depending on where you are located some outdoor trees may be taken indoors for winter storage and they of course survive short indoors exhibitions but keeping a tree indoors for an extended period of time will inevitably kill it.

With this out of the way. Here are my thoughts on this topic after experimenting with this impossible task for a number of years.


Obviously you can't just take any old tree and put it indoors in a tiny pot and expect it to survive. They key here is to choose a suitable species. Think potted houseplants. Tropicals and subtropicals.

What has worked best for me is Ficus microcarpa sometimes sold as "ginseng" ficus. It can take a lot torture, is very forgiving and is a fast grower. The leaves often tends to be a too large to make a good Shohin-sized bonsai but sometimes yo get lucky and can reduce the leaf size.

You can buy a cheap ugly specimen from wherever. Make sure it survives the transition from the store to your home. This means repotting it into good bonsai soil and fertilizing it. When it looks healthy you can brutally reduce the root mass i.e. removing the horrendous tube-like roots and start working towards a nice radial horizontal root spread. This will take a couple of years. If the trunk is ugly you can also cut it back and work towards a tapered look. Otherwise just let it grow. This is a slow process and don't get your hopes up. The initial reduction of the root mass may kill the plant.

When you are happy with the roots and trunk it is finally time to start working on the upper parts of the tree. This is the fun part. Cut off unnecessary branches, cut back to induce backbudding and further ramification. Ficus microcarpa responds well to wiring and after a lot of time, effort and some luck in about 10-15 years you will have something reassembling a Bonsai.

The second best alternative in my opinion is Portulacaria afra. It's a fast grower with tiny leaves and easy to take care for. It can make a pretty good indoor bonsai. The biggest problem is that branches are brittle and can easily break when you try to position them using wire so when possible I suggest shaping the plant via the clip and grow method but this can also be troublesome since the branches tend to grow in very straight angles making it look unnatural and un-tree-like. Nevertheless, this is a good candidate for creating indoor bonsai of the smaller variety.

Bougainvillea is also worth mentioning. I've had mine for many years and it seems to enjoy living indoor which was something I didn't expect. It's a very slow grower so I suggest getting one with a suitable trunk. It's easy to wire and the leaves reduces well. The flowers are beautiful.

Ficus benjamina. I've had mixed results with this one. The leaves are smaller than on its cousin microcarpa and it tends to look more tree-like but they tend to die on me for no apparent reason. For me Ulmus parvifolia, commonly known as the Chinese elm, also falls into this category. Very nice in all respects but out of nowhere they die.

Generally you get at most two windows per year to apply bonsai techniques to your indoor bonsai. The rest of the year you have to focus on their survival.

If you have the option to have your bonsai outdoors during late spring, and late autumn for god sake bring them out.

  • Don't expect great results. Your attempts at indoor bonsai's will never turn out like the stunning trees you see on youtube or instagram. In the best case they will look OK but they will never be able to compete with real outdoor bonsai.

  • It will take a lot of time. Even fast growers grow slowly. You should think in terms of 5 or 10 years when dealing with these plants.

  • It is very hard to achieve good ramification and the leaves will always be a little too big.

  • Don't expect trunks to get any thicker indoors.

  • Defoliation is most often a death sentence to your tree.

  • Think twice about doing larger operations on your trees. While being tolerant they can also be very sensitive to, for example, major root work.

  • Always expect sudden death. Many of your trees will die for no apparent reason. Get used to it. The solution to this is to get many trees and hope that some of them will survive.

  • Grafting techniques doesn't seem to work indoors.

  • Consider investing in an additional light source for your trees. Especially if live in a country with a long and dark winter.

  • Let them rest during autumn to mid-spring. Just water and fertilize. They have enough trouble surviving without you fiddling with them.

  • If the plant works as a houseplant it might work as a bonsai. Your your imagination.

  • Don't bother developing Bonsai from scratch, meaning from seed or very small cuttings. It simply takes too long. Start "big" and reduce.

  • The leaf size will probably always be a bit too large and out of proportion. Leaf size reducing techniques doesn't work as well indoors.

You can actually have indoor bonsai and make them look OK. But it's a long and challenging process filled disappointments along the way. When my best tree died on me I wanted to cry. In short, it can be done, with mediocre results at best. But if you are up for a challenge and is obnoxious and very patient, go for it.

Ambience

I like listening to music but for some weird reason I have a hard time listening to it while I'm studying, working or doing anything that involves some kind of brain power. I prefer total silence but my neighbors are very noisy and I find it hard to be relaxed enough in (semi)public spaces. I'm often stuck with using earplugs + headphones to block out as much noise as possible.

I'm most likely the last person on the internet to discover this but here I present the solution - ambient soundscapes!

Here are some of my favorites:

I usually download the audio from these videos with youtube-dl so I always have offline access. So far this works very well and helps me concentrate and get things done. I'm always on the lookout for new stuff so if you have any suitable recommendations please hit me up.